Make a new urllib package .

It consists of code from urllib, urllib2, urlparse, and robotparser.
The old modules have all been removed.  The new package has five
submodules: urllib.parse, urllib.request, urllib.response,
urllib.error, and urllib.robotparser.  The urllib.request.urlopen()
function uses the url opener from urllib2.

Note that the unittests have not been renamed for the
beta, but they will be renamed in the future.

Joint work with Senthil Kumaran.

6 files changed, 3258 insertions, 0 deletions

diff --git a/Lib/urllib/__init__.py b/Lib/urllib/__init__.py
new file mode 100644
index 0000000000..e69de29bb2
--- /dev/null
+++ b/Lib/urllib/__init__.py
diff --git a/Lib/urllib/error.py b/Lib/urllib/error.py
new file mode 100644
index 0000000000..300c3fe16d
--- /dev/null
+++ b/Lib/urllib/error.py
@@ -0,0 +1,59 @@
+"""Exception classes raised by urllib.
+
+The base exception class is URLError, which inherits from IOError.  It
+doesn't define any behavior of its own, but is the base class for all
+exceptions defined in this package.
+
+HTTPError is an exception class that is also a valid HTTP response
+instance.  It behaves this way because HTTP protocol errors are valid
+responses, with a status code, headers, and a body.  In some contexts,
+an application may want to handle an exception like a regular
+response.
+"""
+
+import urllib.response
+
+# do these error classes make sense?
+# make sure all of the IOError stuff is overridden.  we just want to be
+# subtypes.
+
+class URLError(IOError):
+    # URLError is a sub-type of IOError, but it doesn't share any of
+    # the implementation.  need to override __init__ and __str__.
+    # It sets self.args for compatibility with other EnvironmentError
+    # subclasses, but args doesn't have the typical format with errno in
+    # slot 0 and strerror in slot 1.  This may be better than nothing.
+    def __init__(self, reason, filename=None):
+        self.args = reason,
+        self.reason = reason
+        if filename is not None:
+            self.filename = filename
+
+    def __str__(self):
+        return '<urlopen error %s>' % self.reason
+
+class HTTPError(URLError, urllib.response.addinfourl):
+    """Raised when HTTP error occurs, but also acts like non-error return"""
+    __super_init = urllib.response.addinfourl.__init__
+
+    def __init__(self, url, code, msg, hdrs, fp):
+        self.code = code
+        self.msg = msg
+        self.hdrs = hdrs
+        self.fp = fp
+        self.filename = url
+        # The addinfourl classes depend on fp being a valid file
+        # object.  In some cases, the HTTPError may not have a valid
+        # file object.  If this happens, the simplest workaround is to
+        # not initialize the base classes.
+        if fp is not None:
+            self.__super_init(fp, hdrs, url, code)
+
+    def __str__(self):
+        return 'HTTP Error %s: %s' % (self.code, self.msg)
+
+# exception raised when downloaded size does not match content-length
+class ContentTooShortError(URLError):
+    def __init__(self, message, content):
+        URLError.__init__(self, message)
+        self.content = content
diff --git a/Lib/urllib/parse.py b/Lib/urllib/parse.py
new file mode 100644
index 0000000000..71cc36908d
--- /dev/null
+++ b/Lib/urllib/parse.py
@@ -0,0 +1,630 @@
+"""Parse (absolute and relative) URLs.
+
+See RFC 1808: "Relative Uniform Resource Locators", by R. Fielding,
+UC Irvine, June 1995.
+"""
+
+__all__ = ["urlparse", "urlunparse", "urljoin", "urldefrag",
+           "urlsplit", "urlunsplit"]
+
+# A classification of schemes ('' means apply by default)
+uses_relative = ['ftp', 'http', 'gopher', 'nntp', 'imap',
+                 'wais', 'file', 'https', 'shttp', 'mms',
+                 'prospero', 'rtsp', 'rtspu', '', 'sftp']
+uses_netloc = ['ftp', 'http', 'gopher', 'nntp', 'telnet',
+               'imap', 'wais', 'file', 'mms', 'https', 'shttp',
+               'snews', 'prospero', 'rtsp', 'rtspu', 'rsync', '',
+               'svn', 'svn+ssh', 'sftp']
+non_hierarchical = ['gopher', 'hdl', 'mailto', 'news',
+                    'telnet', 'wais', 'imap', 'snews', 'sip', 'sips']
+uses_params = ['ftp', 'hdl', 'prospero', 'http', 'imap',
+               'https', 'shttp', 'rtsp', 'rtspu', 'sip', 'sips',
+               'mms', '', 'sftp']
+uses_query = ['http', 'wais', 'imap', 'https', 'shttp', 'mms',
+              'gopher', 'rtsp', 'rtspu', 'sip', 'sips', '']
+uses_fragment = ['ftp', 'hdl', 'http', 'gopher', 'news',
+                 'nntp', 'wais', 'https', 'shttp', 'snews',
+                 'file', 'prospero', '']
+
+# Characters valid in scheme names
+scheme_chars = ('abcdefghijklmnopqrstuvwxyz'
+                'ABCDEFGHIJKLMNOPQRSTUVWXYZ'
+                '0123456789'
+                '+-.')
+
+MAX_CACHE_SIZE = 20
+_parse_cache = {}
+
+def clear_cache():
+    """Clear the parse cache."""
+    _parse_cache.clear()
+
+
+class ResultMixin(object):
+    """Shared methods for the parsed result objects."""
+
+    @property
+    def username(self):
+        netloc = self.netloc
+        if "@" in netloc:
+            userinfo = netloc.rsplit("@", 1)[0]
+            if ":" in userinfo:
+                userinfo = userinfo.split(":", 1)[0]
+            return userinfo
+        return None
+
+    @property
+    def password(self):
+        netloc = self.netloc
+        if "@" in netloc:
+            userinfo = netloc.rsplit("@", 1)[0]
+            if ":" in userinfo:
+                return userinfo.split(":", 1)[1]
+        return None
+
+    @property
+    def hostname(self):
+        netloc = self.netloc
+        if "@" in netloc:
+            netloc = netloc.rsplit("@", 1)[1]
+        if ":" in netloc:
+            netloc = netloc.split(":", 1)[0]
+        return netloc.lower() or None
+
+    @property
+    def port(self):
+        netloc = self.netloc
+        if "@" in netloc:
+            netloc = netloc.rsplit("@", 1)[1]
+        if ":" in netloc:
+            port = netloc.split(":", 1)[1]
+            return int(port, 10)
+        return None
+
+from collections import namedtuple
+
+class SplitResult(namedtuple('SplitResult', 'scheme netloc path query fragment'), ResultMixin):
+
+    __slots__ = ()
+
+    def geturl(self):
+        return urlunsplit(self)
+
+
+class ParseResult(namedtuple('ParseResult', 'scheme netloc path params query fragment'), ResultMixin):
+
+    __slots__ = ()
+
+    def geturl(self):
+        return urlunparse(self)
+
+
+def urlparse(url, scheme='', allow_fragments=True):
+    """Parse a URL into 6 components:
+    <scheme>://<netloc>/<path>;<params>?<query>#<fragment>
+    Return a 6-tuple: (scheme, netloc, path, params, query, fragment).
+    Note that we don't break the components up in smaller bits
+    (e.g. netloc is a single string) and we don't expand % escapes."""
+    tuple = urlsplit(url, scheme, allow_fragments)
+    scheme, netloc, url, query, fragment = tuple
+    if scheme in uses_params and ';' in url:
+        url, params = _splitparams(url)
+    else:
+        params = ''
+    return ParseResult(scheme, netloc, url, params, query, fragment)
+
+def _splitparams(url):
+    if '/'  in url:
+        i = url.find(';', url.rfind('/'))
+        if i < 0:
+            return url, ''
+    else:
+        i = url.find(';')
+    return url[:i], url[i+1:]
+
+def _splitnetloc(url, start=0):
+    delim = len(url)   # position of end of domain part of url, default is end
+    for c in '/?#':    # look for delimiters; the order is NOT important
+        wdelim = url.find(c, start)        # find first of this delim
+        if wdelim >= 0:                    # if found
+            delim = min(delim, wdelim)     # use earliest delim position
+    return url[start:delim], url[delim:]   # return (domain, rest)
+
+def urlsplit(url, scheme='', allow_fragments=True):
+    """Parse a URL into 5 components:
+    <scheme>://<netloc>/<path>?<query>#<fragment>
+    Return a 5-tuple: (scheme, netloc, path, query, fragment).
+    Note that we don't break the components up in smaller bits
+    (e.g. netloc is a single string) and we don't expand % escapes."""
+    allow_fragments = bool(allow_fragments)
+    key = url, scheme, allow_fragments, type(url), type(scheme)
+    cached = _parse_cache.get(key, None)
+    if cached:
+        return cached
+    if len(_parse_cache) >= MAX_CACHE_SIZE: # avoid runaway growth
+        clear_cache()
+    netloc = query = fragment = ''
+    i = url.find(':')
+    if i > 0:
+        if url[:i] == 'http': # optimize the common case
+            scheme = url[:i].lower()
+            url = url[i+1:]
+            if url[:2] == '//':
+                netloc, url = _splitnetloc(url, 2)
+            if allow_fragments and '#' in url:
+                url, fragment = url.split('#', 1)
+            if '?' in url:
+                url, query = url.split('?', 1)
+            v = SplitResult(scheme, netloc, url, query, fragment)
+            _parse_cache[key] = v
+            return v
+        for c in url[:i]:
+            if c not in scheme_chars:
+                break
+        else:
+            scheme, url = url[:i].lower(), url[i+1:]
+    if scheme in uses_netloc and url[:2] == '//':
+        netloc, url = _splitnetloc(url, 2)
+    if allow_fragments and scheme in uses_fragment and '#' in url:
+        url, fragment = url.split('#', 1)
+    if scheme in uses_query and '?' in url:
+        url, query = url.split('?', 1)
+    v = SplitResult(scheme, netloc, url, query, fragment)
+    _parse_cache[key] = v
+    return v
+
+def urlunparse(components):
+    """Put a parsed URL back together again.  This may result in a
+    slightly different, but equivalent URL, if the URL that was parsed
+    originally had redundant delimiters, e.g. a ? with an empty query
+    (the draft states that these are equivalent)."""
+    scheme, netloc, url, params, query, fragment = components
+    if params:
+        url = "%s;%s" % (url, params)
+    return urlunsplit((scheme, netloc, url, query, fragment))
+
+def urlunsplit(components):
+    scheme, netloc, url, query, fragment = components
+    if netloc or (scheme and scheme in uses_netloc and url[:2] != '//'):
+        if url and url[:1] != '/': url = '/' + url
+        url = '//' + (netloc or '') + url
+    if scheme:
+        url = scheme + ':' + url
+    if query:
+        url = url + '?' + query
+    if fragment:
+        url = url + '#' + fragment
+    return url
+
+def urljoin(base, url, allow_fragments=True):
+    """Join a base URL and a possibly relative URL to form an absolute
+    interpretation of the latter."""
+    if not base:
+        return url
+    if not url:
+        return base
+    bscheme, bnetloc, bpath, bparams, bquery, bfragment = \
+            urlparse(base, '', allow_fragments)
+    scheme, netloc, path, params, query, fragment = \
+            urlparse(url, bscheme, allow_fragments)
+    if scheme != bscheme or scheme not in uses_relative:
+        return url
+    if scheme in uses_netloc:
+        if netloc:
+            return urlunparse((scheme, netloc, path,
+                               params, query, fragment))
+        netloc = bnetloc
+    if path[:1] == '/':
+        return urlunparse((scheme, netloc, path,
+                           params, query, fragment))
+    if not (path or params or query):
+        return urlunparse((scheme, netloc, bpath,
+                           bparams, bquery, fragment))
+    segments = bpath.split('/')[:-1] + path.split('/')
+    # XXX The stuff below is bogus in various ways...
+    if segments[-1] == '.':
+        segments[-1] = ''
+    while '.' in segments:
+        segments.remove('.')
+    while 1:
+        i = 1
+        n = len(segments) - 1
+        while i < n:
+            if (segments[i] == '..'
+                and segments[i-1] not in ('', '..')):
+                del segments[i-1:i+1]
+                break
+            i = i+1
+        else:
+            break
+    if segments == ['', '..']:
+        segments[-1] = ''
+    elif len(segments) >= 2 and segments[-1] == '..':
+        segments[-2:] = ['']
+    return urlunparse((scheme, netloc, '/'.join(segments),
+                       params, query, fragment))
+
+def urldefrag(url):
+    """Removes any existing fragment from URL.
+
+    Returns a tuple of the defragmented URL and the fragment.  If
+    the URL contained no fragments, the second element is the
+    empty string.
+    """
+    if '#' in url:
+        s, n, p, a, q, frag = urlparse(url)
+        defrag = urlunparse((s, n, p, a, q, ''))
+        return defrag, frag
+    else:
+        return url, ''
+
+
+_hextochr = dict(('%02x' % i, chr(i)) for i in range(256))
+_hextochr.update(('%02X' % i, chr(i)) for i in range(256))
+
+def unquote(s):
+    """unquote('abc%20def') -> 'abc def'."""
+    res = s.split('%')
+    for i in range(1, len(res)):
+        item = res[i]
+        try:
+            res[i] = _hextochr[item[:2]] + item[2:]
+        except KeyError:
+            res[i] = '%' + item
+        except UnicodeDecodeError:
+            res[i] = chr(int(item[:2], 16)) + item[2:]
+    return "".join(res)
+
+def unquote_plus(s):
+    """unquote('%7e/abc+def') -> '~/abc def'"""
+    s = s.replace('+', ' ')
+    return unquote(s)
+
+always_safe = ('ABCDEFGHIJKLMNOPQRSTUVWXYZ'
+               'abcdefghijklmnopqrstuvwxyz'
+               '0123456789' '_.-')
+_safe_quoters= {}
+
+class Quoter:
+    def __init__(self, safe):
+        self.cache = {}
+        self.safe = safe + always_safe
+
+    def __call__(self, c):
+        try:
+            return self.cache[c]
+        except KeyError:
+            if ord(c) < 256:
+                res = (c in self.safe) and c or ('%%%02X' % ord(c))
+                self.cache[c] = res
+                return res
+            else:
+                return "".join(['%%%02X' % i for i in c.encode("utf-8")])
+
+def quote(s, safe = '/'):
+    """quote('abc def') -> 'abc%20def'
+
+    Each part of a URL, e.g. the path info, the query, etc., has a
+    different set of reserved characters that must be quoted.
+
+    RFC 2396 Uniform Resource Identifiers (URI): Generic Syntax lists
+    the following reserved characters.
+
+    reserved    = ";" | "/" | "?" | ":" | "@" | "&" | "=" | "+" |
+                  "$" | ","
+
+    Each of these characters is reserved in some component of a URL,
+    but not necessarily in all of them.
+
+    By default, the quote function is intended for quoting the path
+    section of a URL.  Thus, it will not encode '/'.  This character
+    is reserved, but in typical usage the quote function is being
+    called on a path where the existing slash characters are used as
+    reserved characters.
+    """
+    cachekey = (safe, always_safe)
+    try:
+        quoter = _safe_quoters[cachekey]
+    except KeyError:
+        quoter = Quoter(safe)
+        _safe_quoters[cachekey] = quoter
+    res = map(quoter, s)
+    return ''.join(res)
+
+def quote_plus(s, safe = ''):
+    """Quote the query fragment of a URL; replacing ' ' with '+'"""
+    if ' ' in s:
+        s = quote(s, safe + ' ')
+        return s.replace(' ', '+')
+    return quote(s, safe)
+
+def urlencode(query,doseq=0):
+    """Encode a sequence of two-element tuples or dictionary into a URL query string.
+
+    If any values in the query arg are sequences and doseq is true, each
+    sequence element is converted to a separate parameter.
+
+    If the query arg is a sequence of two-element tuples, the order of the
+    parameters in the output will match the order of parameters in the
+    input.
+    """
+
+    if hasattr(query,"items"):
+        # mapping objects
+        query = query.items()
+    else:
+        # it's a bother at times that strings and string-like objects are
+        # sequences...
+        try:
+            # non-sequence items should not work with len()
+            # non-empty strings will fail this
+            if len(query) and not isinstance(query[0], tuple):
+                raise TypeError
+            # zero-length sequences of all types will get here and succeed,
+            # but that's a minor nit - since the original implementation
+            # allowed empty dicts that type of behavior probably should be
+            # preserved for consistency
+        except TypeError:
+            ty,va,tb = sys.exc_info()
+            raise TypeError("not a valid non-string sequence or mapping object").with_traceback(tb)
+
+    l = []
+    if not doseq:
+        # preserve old behavior
+        for k, v in query:
+            k = quote_plus(str(k))
+            v = quote_plus(str(v))
+            l.append(k + '=' + v)
+    else:
+        for k, v in query:
+            k = quote_plus(str(k))
+            if isinstance(v, str):
+                v = quote_plus(v)
+                l.append(k + '=' + v)
+            elif isinstance(v, str):
+                # is there a reasonable way to convert to ASCII?
+                # encode generates a string, but "replace" or "ignore"
+                # lose information and "strict" can raise UnicodeError
+                v = quote_plus(v.encode("ASCII","replace"))
+                l.append(k + '=' + v)
+            else:
+                try:
+                    # is this a sufficient test for sequence-ness?
+                    x = len(v)
+                except TypeError:
+                    # not a sequence
+                    v = quote_plus(str(v))
+                    l.append(k + '=' + v)
+                else:
+                    # loop over the sequence
+                    for elt in v:
+                        l.append(k + '=' + quote_plus(str(elt)))
+    return '&'.join(l)
+
+# Utilities to parse URLs (most of these return None for missing parts):
+# unwrap('<URL:type://host/path>') --> 'type://host/path'
+# splittype('type:opaquestring') --> 'type', 'opaquestring'
+# splithost('//host[:port]/path') --> 'host[:port]', '/path'
+# splituser('user[:passwd]@host[:port]') --> 'user[:passwd]', 'host[:port]'
+# splitpasswd('user:passwd') -> 'user', 'passwd'
+# splitport('host:port') --> 'host', 'port'
+# splitquery('/path?query') --> '/path', 'query'
+# splittag('/path#tag') --> '/path', 'tag'
+# splitattr('/path;attr1=value1;attr2=value2;...') ->
+#   '/path', ['attr1=value1', 'attr2=value2', ...]
+# splitvalue('attr=value') --> 'attr', 'value'
+# urllib.parse.unquote('abc%20def') -> 'abc def'
+# quote('abc def') -> 'abc%20def')
+
+def toBytes(url):
+    """toBytes(u"URL") --> 'URL'."""
+    # Most URL schemes require ASCII. If that changes, the conversion
+    # can be relaxed.
+    # XXX get rid of toBytes()
+    if isinstance(url, str):
+        try:
+            url = url.encode("ASCII").decode()
+        except UnicodeError:
+            raise UnicodeError("URL " + repr(url) +
+                               " contains non-ASCII characters")
+    return url
+
+def unwrap(url):
+    """unwrap('<URL:type://host/path>') --> 'type://host/path'."""
+    url = str(url).strip()
+    if url[:1] == '<' and url[-1:] == '>':
+        url = url[1:-1].strip()
+    if url[:4] == 'URL:': url = url[4:].strip()
+    return url
+
+_typeprog = None
+def splittype(url):
+    """splittype('type:opaquestring') --> 'type', 'opaquestring'."""
+    global _typeprog
+    if _typeprog is None:
+        import re
+        _typeprog = re.compile('^([^/:]+):')
+
+    match = _typeprog.match(url)
+    if match:
+        scheme = match.group(1)
+        return scheme.lower(), url[len(scheme) + 1:]
+    return None, url
+
+_hostprog = None
+def splithost(url):
+    """splithost('//host[:port]/path') --> 'host[:port]', '/path'."""
+    global _hostprog
+    if _hostprog is None:
+        import re
+        _hostprog = re.compile('^//([^/?]*)(.*)$')
+
+    match = _hostprog.match(url)
+    if match: return match.group(1, 2)
+    return None, url
+
+_userprog = None
+def splituser(host):
+    """splituser('user[:passwd]@host[:port]') --> 'user[:passwd]', 'host[:port]'."""
+    global _userprog
+    if _userprog is None:
+        import re
+        _userprog = re.compile('^(.*)@(.*)$')
+
+    match = _userprog.match(host)
+    if match: return map(unquote, match.group(1, 2))
+    return None, host
+
+_passwdprog = None
+def splitpasswd(user):
+    """splitpasswd('user:passwd') -> 'user', 'passwd'."""
+    global _passwdprog
+    if _passwdprog is None:
+        import re
+        _passwdprog = re.compile('^([^:]*):(.*)$')
+
+    match = _passwdprog.match(user)
+    if match: return match.group(1, 2)
+    return user, None
+
+# splittag('/path#tag') --> '/path', 'tag'
+_portprog = None
+def splitport(host):
+    """splitport('host:port') --> 'host', 'port'."""
+    global _portprog
+    if _portprog is None:
+        import re
+        _portprog = re.compile('^(.*):([0-9]+)$')
+
+    match = _portprog.match(host)
+    if match: return match.group(1, 2)
+    return host, None
+
+_nportprog = None
+def splitnport(host, defport=-1):
+    """Split host and port, returning numeric port.
+    Return given default port if no ':' found; defaults to -1.
+    Return numerical port if a valid number are found after ':'.
+    Return None if ':' but not a valid number."""
+    global _nportprog
+    if _nportprog is None:
+        import re
+        _nportprog = re.compile('^(.*):(.*)$')
+
+    match = _nportprog.match(host)
+    if match:
+        host, port = match.group(1, 2)
+        try:
+            if not port: raise ValueError("no digits")
+            nport = int(port)
+        except ValueError:
+            nport = None
+        return host, nport
+    return host, defport
+
+_queryprog = None
+def splitquery(url):
+    """splitquery('/path?query') --> '/path', 'query'."""
+    global _queryprog
+    if _queryprog is None:
+        import re
+        _queryprog = re.compile('^(.*)\?([^?]*)$')
+
+    match = _queryprog.match(url)
+    if match: return match.group(1, 2)
+    return url, None
+
+_tagprog = None
+def splittag(url):
+    """splittag('/path#tag') --> '/path', 'tag'."""
+    global _tagprog
+    if _tagprog is None:
+        import re
+        _tagprog = re.compile('^(.*)#([^#]*)$')
+
+    match = _tagprog.match(url)
+    if match: return match.group(1, 2)
+    return url, None
+
+def splitattr(url):
+    """splitattr('/path;attr1=value1;attr2=value2;...') ->
+        '/path', ['attr1=value1', 'attr2=value2', ...]."""
+    words = url.split(';')
+    return words[0], words[1:]
+
+_valueprog = None
+def splitvalue(attr):
+    """splitvalue('attr=value') --> 'attr', 'value'."""
+    global _valueprog
+    if _valueprog is None:
+        import re
+        _valueprog = re.compile('^([^=]*)=(.*)$')
+
+    match = _valueprog.match(attr)
+    if match: return match.group(1, 2)
+    return attr, None
+
+test_input = """
+      http://a/b/c/d
+
+      g:h        = <URL:g:h>
+      http:g     = <URL:http://a/b/c/g>
+      http:      = <URL:http://a/b/c/d>
+      g          = <URL:http://a/b/c/g>
+      ./g        = <URL:http://a/b/c/g>
+      g/         = <URL:http://a/b/c/g/>
+      /g         = <URL:http://a/g>
+      //g        = <URL:http://g>
+      ?y         = <URL:http://a/b/c/d?y>
+      g?y        = <URL:http://a/b/c/g?y>
+      g?y/./x    = <URL:http://a/b/c/g?y/./x>
+      .          = <URL:http://a/b/c/>
+      ./         = <URL:http://a/b/c/>
+      ..         = <URL:http://a/b/>
+      ../        = <URL:http://a/b/>
+      ../g       = <URL:http://a/b/g>
+      ../..      = <URL:http://a/>
+      ../../g    = <URL:http://a/g>
+      ../../../g = <URL:http://a/../g>
+      ./../g     = <URL:http://a/b/g>
+      ./g/.      = <URL:http://a/b/c/g/>
+      /./g       = <URL:http://a/./g>
+      g/./h      = <URL:http://a/b/c/g/h>
+      g/../h     = <URL:http://a/b/c/h>
+      http:g     = <URL:http://a/b/c/g>
+      http:      = <URL:http://a/b/c/d>
+      http:?y         = <URL:http://a/b/c/d?y>
+      http:g?y        = <URL:http://a/b/c/g?y>
+      http:g?y/./x    = <URL:http://a/b/c/g?y/./x>
+"""
+
+def test():
+    import sys
+    base = ''
+    if sys.argv[1:]:
+        fn = sys.argv[1]
+        if fn == '-':
+            fp = sys.stdin
+        else:
+            fp = open(fn)
+    else:
+        from io import StringIO
+        fp = StringIO(test_input)
+    for line in fp:
+        words = line.split()
+        if not words:
+            continue
+        url = words[0]
+        parts = urlparse(url)
+        print('%-10s : %s' % (url, parts))
+        abs = urljoin(base, url)
+        if not base:
+            base = abs
+        wrapped = '<URL:%s>' % abs
+        print('%-10s = %s' % (url, wrapped))
+        if len(words) == 3 and words[1] == '=':
+            if wrapped != words[2]:
+                print('EXPECTED', words[2], '!!!!!!!!!!')
+
+if __name__ == '__main__':
+    test()
diff --git a/Lib/urllib/request.py b/Lib/urllib/request.py
new file mode 100644
index 0000000000..cd4729a95e
--- /dev/null
+++ b/Lib/urllib/request.py
@@ -0,0 +1,2295 @@
+# Issues in merging urllib and urllib2:
+# 1. They both define a function named urlopen()
+
+"""An extensible library for opening URLs using a variety of protocols
+
+The simplest way to use this module is to call the urlopen function,
+which accepts a string containing a URL or a Request object (described
+below).  It opens the URL and returns the results as file-like
+object; the returned object has some extra methods described below.
+
+The OpenerDirector manages a collection of Handler objects that do
+all the actual work.  Each Handler implements a particular protocol or
+option.  The OpenerDirector is a composite object that invokes the
+Handlers needed to open the requested URL.  For example, the
+HTTPHandler performs HTTP GET and POST requests and deals with
+non-error returns.  The HTTPRedirectHandler automatically deals with
+HTTP 301, 302, 303 and 307 redirect errors, and the HTTPDigestAuthHandler
+deals with digest authentication.
+
+urlopen(url, data=None) -- Basic usage is the same as original
+urllib.  pass the url and optionally data to post to an HTTP URL, and
+get a file-like object back.  One difference is that you can also pass
+a Request instance instead of URL.  Raises a URLError (subclass of
+IOError); for HTTP errors, raises an HTTPError, which can also be
+treated as a valid response.
+
+build_opener -- Function that creates a new OpenerDirector instance.
+Will install the default handlers.  Accepts one or more Handlers as
+arguments, either instances or Handler classes that it will
+instantiate.  If one of the argument is a subclass of the default
+handler, the argument will be installed instead of the default.
+
+install_opener -- Installs a new opener as the default opener.
+
+objects of interest:
+OpenerDirector --
+
+Request -- An object that encapsulates the state of a request.  The
+state can be as simple as the URL.  It can also include extra HTTP
+headers, e.g. a User-Agent.
+
+BaseHandler --
+
+internals:
+BaseHandler and parent
+_call_chain conventions
+
+Example usage:
+
+import urllib2
+
+# set up authentication info
+authinfo = urllib2.HTTPBasicAuthHandler()
+authinfo.add_password(realm='PDQ Application',
+                      uri='https://mahler:8092/site-updates.py',
+                      user='klem',
+                      passwd='geheim$parole')
+
+proxy_support = urllib2.ProxyHandler({"http" : "http://ahad-haam:3128"})
+
+# build a new opener that adds authentication and caching FTP handlers
+opener = urllib2.build_opener(proxy_support, authinfo, urllib2.CacheFTPHandler)
+
+# install it
+urllib2.install_opener(opener)
+
+f = urllib2.urlopen('http://www.python.org/')
+"""
+
+# XXX issues:
+# If an authentication error handler that tries to perform
+# authentication for some reason but fails, how should the error be
+# signalled?  The client needs to know the HTTP error code.  But if
+# the handler knows that the problem was, e.g., that it didn't know
+# that hash algo that requested in the challenge, it would be good to
+# pass that information along to the client, too.
+# ftp errors aren't handled cleanly
+# check digest against correct (i.e. non-apache) implementation
+
+# Possible extensions:
+# complex proxies  XXX not sure what exactly was meant by this
+# abstract factory for opener
+
+import base64
+import email
+import hashlib
+import http.client
+import io
+import os
+import posixpath
+import random
+import re
+import socket
+import sys
+import time
+import urllib.parse, urllib.error, urllib.response
+import bisect
+
+from io import StringIO
+
+# check for SSL
+try:
+    import ssl
+except:
+    _have_ssl = False
+else:
+    _have_ssl = True
+assert _have_ssl
+
+# used in User-Agent header sent
+__version__ = sys.version[:3]
+
+_opener = None
+def urlopen(url, data=None, timeout=socket._GLOBAL_DEFAULT_TIMEOUT):
+    global _opener
+    if _opener is None:
+        _opener = build_opener()
+    return _opener.open(url, data, timeout)
+
+def install_opener(opener):
+    global _opener
+    _opener = opener
+
+# TODO(jhylton): Make this work with the same global opener.
+_urlopener = None
+def urlretrieve(url, filename=None, reporthook=None, data=None):
+    global _urlopener
+    if not _urlopener:
+        _urlopener = FancyURLopener()
+    return _urlopener.retrieve(url, filename, reporthook, data)
+
+def urlcleanup():
+    if _urlopener:
+        _urlopener.cleanup()
+    global _opener
+    if _opener:
+        _opener = None
+
+# copied from cookielib.py
+_cut_port_re = re.compile(r":\d+$")
+def request_host(request):
+    """Return request-host, as defined by RFC 2965.
+
+    Variation from RFC: returned value is lowercased, for convenient
+    comparison.
+
+    """
+    url = request.get_full_url()
+    host = urllib.parse.urlparse(url)[1]
+    if host == "":
+        host = request.get_header("Host", "")
+
+    # remove port, if present
+    host = _cut_port_re.sub("", host, 1)
+    return host.lower()
+
+class Request:
+
+    def __init__(self, url, data=None, headers={},
+                 origin_req_host=None, unverifiable=False):
+        # unwrap('<URL:type://host/path>') --> 'type://host/path'
+        self.__original = urllib.parse.unwrap(url)
+        self.type = None
+        # self.__r_type is what's left after doing the splittype
+        self.host = None
+        self.port = None
+        self.data = data
+        self.headers = {}
+        for key, value in headers.items():
+            self.add_header(key, value)
+        self.unredirected_hdrs = {}
+        if origin_req_host is None:
+            origin_req_host = request_host(self)
+        self.origin_req_host = origin_req_host
+        self.unverifiable = unverifiable
+
+    def __getattr__(self, attr):
+        # XXX this is a fallback mechanism to guard against these
+        # methods getting called in a non-standard order.  this may be
+        # too complicated and/or unnecessary.
+        # XXX should the __r_XXX attributes be public?
+        if attr[:12] == '_Request__r_':
+            name = attr[12:]
+            if hasattr(Request, 'get_' + name):
+                getattr(self, 'get_' + name)()
+                return getattr(self, attr)
+        raise AttributeError(attr)
+
+    def get_method(self):
+        if self.has_data():
+            return "POST"
+        else:
+            return "GET"
+
+    # XXX these helper methods are lame
+
+    def add_data(self, data):
+        self.data = data
+
+    def has_data(self):
+        return self.data is not None
+
+    def get_data(self):
+        return self.data
+
+    def get_full_url(self):
+        return self.__original
+
+    def get_type(self):
+        if self.type is None:
+            self.type, self.__r_type = urllib.parse.splittype(self.__original)
+            if self.type is None:
+                raise ValueError("unknown url type: %s" % self.__original)
+        return self.type
+
+    def get_host(self):
+        if self.host is None:
+            self.host, self.__r_host = urllib.parse.splithost(self.__r_type)
+            if self.host:
+                self.host = urllib.parse.unquote(self.host)
+        return self.host
+
+    def get_selector(self):
+        return self.__r_host
+
+    def set_proxy(self, host, type):
+        self.host, self.type = host, type
+        self.__r_host = self.__original
+
+    def get_origin_req_host(self):
+        return self.origin_req_host
+
+    def is_unverifiable(self):
+        return self.unverifiable
+
+    def add_header(self, key, val):
+        # useful for something like authentication
+        self.headers[key.capitalize()] = val
+
+    def add_unredirected_header(self, key, val):
+        # will not be added to a redirected request
+        self.unredirected_hdrs[key.capitalize()] = val
+
+    def has_header(self, header_name):
+        return (header_name in self.headers or
+                header_name in self.unredirected_hdrs)
+
+    def get_header(self, header_name, default=None):
+        return self.headers.get(
+            header_name,
+            self.unredirected_hdrs.get(header_name, default))
+
+    def header_items(self):
+        hdrs = self.unredirected_hdrs.copy()
+        hdrs.update(self.headers)
+        return list(hdrs.items())
+
+class OpenerDirector:
+    def __init__(self):
+        client_version = "Python-urllib/%s" % __version__
+        self.addheaders = [('User-agent', client_version)]
+        # manage the individual handlers
+        self.handlers = []
+        self.handle_open = {}
+        self.handle_error = {}
+        self.process_response = {}
+        self.process_request = {}
+
+    def add_handler(self, handler):
+        if not hasattr(handler, "add_parent"):
+            raise TypeError("expected BaseHandler instance, got %r" %
+                            type(handler))
+
+        added = False
+        for meth in dir(handler):
+            if meth in ["redirect_request", "do_open", "proxy_open"]:
+                # oops, coincidental match
+                continue
+
+            i = meth.find("_")
+            protocol = meth[:i]
+            condition = meth[i+1:]
+
+            if condition.startswith("error"):
+                j = condition.find("_") + i + 1
+                kind = meth[j+1:]
+                try:
+                    kind = int(kind)
+                except ValueError:
+                    pass
+                lookup = self.handle_error.get(protocol, {})
+                self.handle_error[protocol] = lookup
+            elif condition == "open":
+                kind = protocol
+                lookup = self.handle_open
+            elif condition == "response":
+                kind = protocol
+                lookup = self.process_response
+            elif condition == "request":
+                kind = protocol
+                lookup = self.process_request
+            else:
+                continue
+
+            handlers = lookup.setdefault(kind, [])
+            if handlers:
+                bisect.insort(handlers, handler)
+            else:
+                handlers.append(handler)
+            added = True
+
+        if added:
+            # the handlers must work in an specific order, the order
+            # is specified in a Handler attribute
+            bisect.insort(self.handlers, handler)
+            handler.add_parent(self)
+
+    def close(self):
+        # Only exists for backwards compatibility.
+        pass
+
+    def _call_chain(self, chain, kind, meth_name, *args):
+        # Handlers raise an exception if no one else should try to handle
+        # the request, or return None if they can't but another handler
+        # could.  Otherwise, they return the response.
+        handlers = chain.get(kind, ())
+        for handler in handlers:
+            func = getattr(handler, meth_name)
+
+            result = func(*args)
+            if result is not None:
+                return result
+
+    def open(self, fullurl, data=None, timeout=socket._GLOBAL_DEFAULT_TIMEOUT):
+        # accept a URL or a Request object
+        if isinstance(fullurl, str):
+            req = Request(fullurl, data)
+        else:
+            req = fullurl
+            if data is not None:
+                req.add_data(data)
+
+        req.timeout = timeout
+        protocol = req.get_type()
+
+        # pre-process request
+        meth_name = protocol+"_request"
+        for processor in self.process_request.get(protocol, []):
+            meth = getattr(processor, meth_name)
+            req = meth(req)
+
+        response = self._open(req, data)
+
+        # post-process response
+        meth_name = protocol+"_response"
+        for processor in self.process_response.get(protocol, []):
+            meth = getattr(processor, meth_name)
+            response = meth(req, response)
+
+        return response
+
+    def _open(self, req, data=None):
+        result = self._call_chain(self.handle_open, 'default',
+                                  'default_open', req)
+        if result:
+            return result
+
+        protocol = req.get_type()
+        result = self._call_chain(self.handle_open, protocol, protocol +
+                                  '_open', req)
+        if result:
+            return result
+
+        return self._call_chain(self.handle_open, 'unknown',
+                                'unknown_open', req)
+
+    def error(self, proto, *args):
+        if proto in ('http', 'https'):
+            # XXX http[s] protocols are special-cased
+            dict = self.handle_error['http'] # https is not different than http
+            proto = args[2]  # YUCK!
+            meth_name = 'http_error_%s' % proto
+            http_err = 1
+            orig_args = args
+        else:
+            dict = self.handle_error
+            meth_name = proto + '_error'
+            http_err = 0
+        args = (dict, proto, meth_name) + args
+        result = self._call_chain(*args)
+        if result:
+            return result
+
+        if http_err:
+            args = (dict, 'default', 'http_error_default') + orig_args
+            return self._call_chain(*args)
+
+# XXX probably also want an abstract factory that knows when it makes
+# sense to skip a superclass in favor of a subclass and when it might
+# make sense to include both
+
+def build_opener(*handlers):
+    """Create an opener object from a list of handlers.
+
+    The opener will use several default handlers, including support
+    for HTTP and FTP.
+
+    If any of the handlers passed as arguments are subclasses of the
+    default handlers, the default handlers will not be used.
+    """
+    def isclass(obj):
+        return isinstance(obj, type) or hasattr(obj, "__bases__")
+
+    opener = OpenerDirector()
+    default_classes = [ProxyHandler, UnknownHandler, HTTPHandler,
+                       HTTPDefaultErrorHandler, HTTPRedirectHandler,
+                       FTPHandler, FileHandler, HTTPErrorProcessor]
+    if hasattr(http.client, "HTTPSConnection"):
+        default_classes.append(HTTPSHandler)
+    else:
+        import pdb; pdb.set_trace()
+    skip = set()
+    for klass in default_classes:
+        for check in handlers:
+            if isclass(check):
+                if issubclass(check, klass):
+                    skip.add(klass)
+            elif isinstance(check, klass):
+                skip.add(klass)
+    for klass in skip:
+        default_classes.remove(klass)
+
+    for klass in default_classes:
+        opener.add_handler(klass())
+
+    for h in handlers:
+        if isclass(h):
+            h = h()
+        opener.add_handler(h)
+    return opener
+
+class BaseHandler:
+    handler_order = 500
+
+    def add_parent(self, parent):
+        self.parent = parent
+
+    def close(self):
+        # Only exists for backwards compatibility
+        pass
+
+    def __lt__(self, other):
+        if not hasattr(other, "handler_order"):
+            # Try to preserve the old behavior of having custom classes
+            # inserted after default ones (works only for custom user
+            # classes which are not aware of handler_order).
+            return True
+        return self.handler_order < other.handler_order
+
+
+class HTTPErrorProcessor(BaseHandler):
+    """Process HTTP error responses."""
+    handler_order = 1000  # after all other processing
+
+    def http_response(self, request, response):
+        code, msg, hdrs = response.code, response.msg, response.info()
+
+        # According to RFC 2616, "2xx" code indicates that the client's
+        # request was successfully received, understood, and accepted.
+        if not (200 <= code < 300):
+            response = self.parent.error(
+                'http', request, response, code, msg, hdrs)
+
+        return response
+
+    https_response = http_response
+
+class HTTPDefaultErrorHandler(BaseHandler):
+    def http_error_default(self, req, fp, code, msg, hdrs):
+        raise urllib.error.HTTPError(req.get_full_url(), code, msg, hdrs, fp)
+
+class HTTPRedirectHandler(BaseHandler):
+    # maximum number of redirections to any single URL
+    # this is needed because of the state that cookies introduce
+    max_repeats = 4
+    # maximum total number of redirections (regardless of URL) before
+    # assuming we're in a loop
+    max_redirections = 10
+
+    def redirect_request(self, req, fp, code, msg, headers, newurl):
+        """Return a Request or None in response to a redirect.
+
+        This is called by the http_error_30x methods when a
+        redirection response is received.  If a redirection should
+        take place, return a new Request to allow http_error_30x to
+        perform the redirect.  Otherwise, raise HTTPError if no-one
+        else should try to handle this url.  Return None if you can't
+        but another Handler might.
+        """
+        m = req.get_method()
+        if (not (code in (301, 302, 303, 307) and m in ("GET", "HEAD")
+            or code in (301, 302, 303) and m == "POST")):
+            raise urllib.error.HTTPError(req.get_full_url(),
+                                         code, msg, headers, fp)
+
+        # Strictly (according to RFC 2616), 301 or 302 in response to
+        # a POST MUST NOT cause a redirection without confirmation
+        # from the user (of urllib2, in this case).  In practice,
+        # essentially all clients do redirect in this case, so we do
+        # the same.
+        # be conciliant with URIs containing a space
+        newurl = newurl.replace(' ', '%20')
+        CONTENT_HEADERS = ("content-length", "content-type")
+        newheaders = dict((k, v) for k, v in req.headers.items()
+                          if k.lower() not in CONTENT_HEADERS)
+        return Request(newurl,
+                       headers=newheaders,
+                       origin_req_host=req.get_origin_req_host(),
+                       unverifiable=True)
+
+    # Implementation note: To avoid the server sending us into an
+    # infinite loop, the request object needs to track what URLs we
+    # have already seen.  Do this by adding a handler-specific
+    # attribute to the Request object.
+    def http_error_302(self, req, fp, code, msg, headers):
+        # Some servers (incorrectly) return multiple Location headers
+        # (so probably same goes for URI).  Use first header.
+        if "location" in headers:
+            newurl = headers["location"]
+        elif "uri" in headers:
+            newurl = headers["uri"]
+        else:
+            return
+        newurl = urllib.parse.urljoin(req.get_full_url(), newurl)
+
+        # XXX Probably want to forget about the state of the current
+        # request, although that might interact poorly with other
+        # handlers that also use handler-specific request attributes
+        new = self.redirect_request(req, fp, code, msg, headers, newurl)
+        if new is None:
+            return
+
+        # loop detection
+        # .redirect_dict has a key url if url was previously visited.
+        if hasattr(req, 'redirect_dict'):
+            visited = new.redirect_dict = req.redirect_dict
+            if (visited.get(newurl, 0) >= self.max_repeats or
+                len(visited) >= self.max_redirections):
+                raise urllib.error.HTTPError(req.get_full_url(), code,
+                                             self.inf_msg + msg, headers, fp)
+        else:
+            visited = new.redirect_dict = req.redirect_dict = {}
+        visited[newurl] = visited.get(newurl, 0) + 1
+
+        # Don't close the fp until we are sure that we won't use it
+        # with HTTPError.
+        fp.read()
+        fp.close()
+
+        return self.parent.open(new)
+
+    http_error_301 = http_error_303 = http_error_307 = http_error_302
+
+    inf_msg = "The HTTP server returned a redirect error that would " \
+              "lead to an infinite loop.\n" \
+              "The last 30x error message was:\n"
+
+
+def _parse_proxy(proxy):
+    """Return (scheme, user, password, host/port) given a URL or an authority.
+
+    If a URL is supplied, it must have an authority (host:port) component.
+    According to RFC 3986, having an authority component means the URL must
+    have two slashes after the scheme:
+
+    >>> _parse_proxy('file:/ftp.example.com/')
+    Traceback (most recent call last):
+    ValueError: proxy URL with no authority: 'file:/ftp.example.com/'
+
+    The first three items of the returned tuple may be None.
+
+    Examples of authority parsing:
+
+    >>> _parse_proxy('proxy.example.com')
+    (None, None, None, 'proxy.example.com')
+    >>> _parse_proxy('proxy.example.com:3128')
+    (None, None, None, 'proxy.example.com:3128')
+
+    The authority component may optionally include userinfo (assumed to be
+    username:password):
+
+    >>> _parse_proxy('joe:password@proxy.example.com')
+    (None, 'joe', 'password', 'proxy.example.com')
+    >>> _parse_proxy('joe:password@proxy.example.com:3128')
+    (None, 'joe', 'password', 'proxy.example.com:3128')
+
+    Same examples, but with URLs instead:
+
+    >>> _parse_proxy('http://proxy.example.com/')
+    ('http', None, None, 'proxy.example.com')
+    >>> _parse_proxy('http://proxy.example.com:3128/')
+    ('http', None, None, 'proxy.example.com:3128')
+    >>> _parse_proxy('http://joe:password@proxy.example.com/')
+    ('http', 'joe', 'password', 'proxy.example.com')
+    >>> _parse_proxy('http://joe:password@proxy.example.com:3128')
+    ('http', 'joe', 'password', 'proxy.example.com:3128')
+
+    Everything after the authority is ignored:
+
+    >>> _parse_proxy('ftp://joe:password@proxy.example.com/rubbish:3128')
+    ('ftp', 'joe', 'password', 'proxy.example.com')
+
+    Test for no trailing '/' case:
+
+    >>> _parse_proxy('http://joe:password@proxy.example.com')
+    ('http', 'joe', 'password', 'proxy.example.com')
+
+    """
+    scheme, r_scheme = urllib.parse.splittype(proxy)
+    if not r_scheme.startswith("/"):
+        # authority
+        scheme = None
+        authority = proxy
+    else:
+        # URL
+        if not r_scheme.startswith("//"):
+            raise ValueError("proxy URL with no authority: %r" % proxy)
+        # We have an authority, so for RFC 3986-compliant URLs (by ss 3.
+        # and 3.3.), path is empty or starts with '/'
+        end = r_scheme.find("/", 2)
+        if end == -1:
+            end = None
+        authority = r_scheme[2:end]
+    userinfo, hostport = urllib.parse.splituser(authority)
+    if userinfo is not None:
+        user, password = urllib.parse.splitpasswd(userinfo)
+    else:
+        user = password = None
+    return scheme, user, password, hostport
+
+class ProxyHandler(BaseHandler):
+    # Proxies must be in front
+    handler_order = 100
+
+    def __init__(self, proxies=None):
+        if proxies is None:
+            proxies = getproxies()
+        assert hasattr(proxies, 'keys'), "proxies must be a mapping"
+        self.proxies = proxies
+        for type, url in proxies.items():
+            setattr(self, '%s_open' % type,
+                    lambda r, proxy=url, type=type, meth=self.proxy_open: \
+                    meth(r, proxy, type))
+
+    def proxy_open(self, req, proxy, type):
+        orig_type = req.get_type()
+        proxy_type, user, password, hostport = _parse_proxy(proxy)
+        if proxy_type is None:
+            proxy_type = orig_type
+        if user and password:
+            user_pass = '%s:%s' % (unquote(user),
+                                   urllib.parse.unquote(password))
+            creds = base64.b64encode(user_pass.encode()).decode("ascii")
+            req.add_header('Proxy-authorization', 'Basic ' + creds)
+        hostport = urllib.parse.unquote(hostport)
+        req.set_proxy(hostport, proxy_type)
+        if orig_type == proxy_type:
+            # let other handlers take care of it
+            return None
+        else:
+            # need to start over, because the other handlers don't
+            # grok the proxy's URL type
+            # e.g. if we have a constructor arg proxies like so:
+            # {'http': 'ftp://proxy.example.com'}, we may end up turning
+            # a request for http://acme.example.com/a into one for
+            # ftp://proxy.example.com/a
+            return self.parent.open(req)
+
+class HTTPPasswordMgr:
+
+    def __init__(self):
+        self.passwd = {}
+
+    def add_password(self, realm, uri, user, passwd):
+        # uri could be a single URI or a sequence
+        if isinstance(uri, str):
+            uri = [uri]
+        if not realm in self.passwd:
+            self.passwd[realm] = {}
+        for default_port in True, False:
+            reduced_uri = tuple(
+                [self.reduce_uri(u, default_port) for u in uri])
+            self.passwd[realm][reduced_uri] = (user, passwd)
+
+    def find_user_password(self, realm, authuri):
+        domains = self.passwd.get(realm, {})
+        for default_port in True, False:
+            reduced_authuri = self.reduce_uri(authuri, default_port)
+            for uris, authinfo in domains.items():
+                for uri in uris:
+                    if self.is_suburi(uri, reduced_authuri):
+                        return authinfo
+        return None, None
+
+    def reduce_uri(self, uri, default_port=True):
+        """Accept authority or URI and extract only the authority and path."""
+        # note HTTP URLs do not have a userinfo component
+        parts = urllib.parse.urlsplit(uri)
+        if parts[1]:
+            # URI
+            scheme = parts[0]
+            authority = parts[1]
+            path = parts[2] or '/'
+        else:
+            # host or host:port
+            scheme = None
+            authority = uri
+            path = '/'
+        host, port = urllib.parse.splitport(authority)
+        if default_port and port is None and scheme is not None:
+            dport = {"http": 80,
+                     "https": 443,
+                     }.get(scheme)
+            if dport is not None:
+                authority = "%s:%d" % (host, dport)
+        return authority, path
+
+    def is_suburi(self, base, test):
+        """Check if test is below base in a URI tree
+
+        Both args must be URIs in reduced form.
+        """
+        if base == test:
+            return True
+        if base[0] != test[0]:
+            return False
+        common = posixpath.commonprefix((base[1], test[1]))
+        if len(common) == len(base[1]):
+            return True
+        return False
+
+
+class HTTPPasswordMgrWithDefaultRealm(HTTPPasswordMgr):
+
+    def find_user_password(self, realm, authuri):
+        user, password = HTTPPasswordMgr.find_user_password(self, realm,
+                                                            authuri)
+        if user is not None:
+            return user, password
+        return HTTPPasswordMgr.find_user_password(self, None, authuri)
+
+
+class AbstractBasicAuthHandler:
+
+    # XXX this allows for multiple auth-schemes, but will stupidly pick
+    # the last one with a realm specified.
+
+    # allow for double- and single-quoted realm values
+    # (single quotes are a violation of the RFC, but appear in the wild)
+    rx = re.compile('(?:.*,)*[ \t]*([^ \t]+)[ \t]+'
+                    'realm=(["\'])(.*?)\\2', re.I)
+
+    # XXX could pre-emptively send auth info already accepted (RFC 2617,
+    # end of section 2, and section 1.2 immediately after "credentials"
+    # production).
+
+    def __init__(self, password_mgr=None):
+        if password_mgr is None:
+            password_mgr = HTTPPasswordMgr()
+        self.passwd = password_mgr
+        self.add_password = self.passwd.add_password
+
+    def http_error_auth_reqed(self, authreq, host, req, headers):
+        # host may be an authority (without userinfo) or a URL with an
+        # authority
+        # XXX could be multiple headers
+        authreq = headers.get(authreq, None)
+        if authreq:
+            mo = AbstractBasicAuthHandler.rx.search(authreq)
+            if mo:
+                scheme, quote, realm = mo.groups()
+                if scheme.lower() == 'basic':
+                    return self.retry_http_basic_auth(host, req, realm)
+
+    def retry_http_basic_auth(self, host, req, realm):
+        user, pw = self.passwd.find_user_password(realm, host)
+        if pw is not None:
+            raw = "%s:%s" % (user, pw)
+            auth = "Basic " + base64.b64encode(raw.encode()).decode("ascii")
+            if req.headers.get(self.auth_header, None) == auth:
+                return None
+            req.add_header(self.auth_header, auth)
+            return self.parent.open(req)
+        else:
+            return None
+
+
+class HTTPBasicAuthHandler(AbstractBasicAuthHandler, BaseHandler):
+
+    auth_header = 'Authorization'
+
+    def http_error_401(self, req, fp, code, msg, headers):
+        url = req.get_full_url()
+        return self.http_error_auth_reqed('www-authenticate',
+                                          url, req, headers)
+
+
+class ProxyBasicAuthHandler(AbstractBasicAuthHandler, BaseHandler):
+
+    auth_header = 'Proxy-authorization'
+
+    def http_error_407(self, req, fp, code, msg, headers):
+        # http_error_auth_reqed requires that there is no userinfo component in
+        # authority.  Assume there isn't one, since urllib2 does not (and
+        # should not, RFC 3986 s. 3.2.1) support requests for URLs containing
+        # userinfo.
+        authority = req.get_host()
+        return self.http_error_auth_reqed('proxy-authenticate',
+                                          authority, req, headers)
+
+
+def randombytes(n):
+    """Return n random bytes."""
+    return os.urandom(n)
+
+class AbstractDigestAuthHandler:
+    # Digest authentication is specified in RFC 2617.
+
+    # XXX The client does not inspect the Authentication-Info header
+    # in a successful response.
+
+    # XXX It should be possible to test this implementation against
+    # a mock server that just generates a static set of challenges.
+
+    # XXX qop="auth-int" supports is shaky
+
+    def __init__(self, passwd=None):
+        if passwd is None:
+            passwd = HTTPPasswordMgr()
+        self.passwd = passwd
+        self.add_password = self.passwd.add_password
+        self.retried = 0
+        self.nonce_count = 0
+
+    def reset_retry_count(self):
+        self.retried = 0
+
+    def http_error_auth_reqed(self, auth_header, host, req, headers):
+        authreq = headers.get(auth_header, None)
+        if self.retried > 5:
+            # Don't fail endlessly - if we failed once, we'll probably
+            # fail a second time. Hm. Unless the Password Manager is
+            # prompting for the information. Crap. This isn't great
+            # but it's better than the current 'repeat until recursion
+            # depth exceeded' approach <wink>
+            raise urllib.error.HTTPError(req.get_full_url(), 401,
+                                         "digest auth failed",
+                                         headers, None)
+        else:
+            self.retried += 1
+        if authreq:
+            scheme = authreq.split()[0]
+            if scheme.lower() == 'digest':
+                return self.retry_http_digest_auth(req, authreq)
+
+    def retry_http_digest_auth(self, req, auth):
+        token, challenge = auth.split(' ', 1)
+        chal = parse_keqv_list(filter(None, parse_http_list(challenge)))
+        auth = self.get_authorization(req, chal)
+        if auth:
+            auth_val = 'Digest %s' % auth
+            if req.headers.get(self.auth_header, None) == auth_val:
+                return None
+            req.add_unredirected_header(self.auth_header, auth_val)
+            resp = self.parent.open(req)
+            return resp
+
+    def get_cnonce(self, nonce):
+        # The cnonce-value is an opaque
+        # quoted string value provided by the client and used by both client
+        # and server to avoid chosen plaintext attacks, to provide mutual
+        # authentication, and to provide some message integrity protection.
+        # This isn't a fabulous effort, but it's probably Good Enough.
+        s = "%s:%s:%s:" % (self.nonce_count, nonce, time.ctime())
+        b = s.encode("ascii") + randombytes(8)
+        dig = hashlib.sha1(b).hexdigest()
+        return dig[:16]
+
+    def get_authorization(self, req, chal):
+        try:
+            realm = chal['realm']
+            nonce = chal['nonce']
+            qop = chal.get('qop')
+            algorithm = chal.get('algorithm', 'MD5')
+            # mod_digest doesn't send an opaque, even though it isn't
+            # supposed to be optional
+            opaque = chal.get('opaque', None)
+        except KeyError:
+            return None
+
+        H, KD = self.get_algorithm_impls(algorithm)
+        if H is None:
+            return None
+
+        user, pw = self.passwd.find_user_password(realm, req.get_full_url())
+        if user is None:
+            return None
+
+        # XXX not implemented yet
+        if req.has_data():
+            entdig = self.get_entity_digest(req.get_data(), chal)
+        else:
+            entdig = None
+
+        A1 = "%s:%s:%s" % (user, realm, pw)
+        A2 = "%s:%s" % (req.get_method(),
+                        # XXX selector: what about proxies and full urls
+                        req.get_selector())
+        if qop == 'auth':
+            self.nonce_count += 1
+            ncvalue = '%08x' % self.nonce_count
+            cnonce = self.get_cnonce(nonce)
+            noncebit = "%s:%s:%s:%s:%s" % (nonce, ncvalue, cnonce, qop, H(A2))
+            respdig = KD(H(A1), noncebit)
+        elif qop is None:
+            respdig = KD(H(A1), "%s:%s" % (nonce, H(A2)))
+        else:
+            # XXX handle auth-int.
+            raise urllib.error.URLError("qop '%s' is not supported." % qop)
+
+        # XXX should the partial digests be encoded too?
+
+        base = 'username="%s", realm="%s", nonce="%s", uri="%s", ' \
+               'response="%s"' % (user, realm, nonce, req.get_selector(),
+                                  respdig)
+        if opaque:
+            base += ', opaque="%s"' % opaque
+        if entdig:
+            base += ', digest="%s"' % entdig
+        base += ', algorithm="%s"' % algorithm
+        if qop:
+            base += ', qop=auth, nc=%s, cnonce="%s"' % (ncvalue, cnonce)
+        return base
+
+    def get_algorithm_impls(self, algorithm):
+        # lambdas assume digest modules are imported at the top level
+        if algorithm == 'MD5':
+            H = lambda x: hashlib.md5(x.encode("ascii")).hexdigest()
+        elif algorithm == 'SHA':
+            H = lambda x: hashlib.sha1(x.encode("ascii")).hexdigest()
+        # XXX MD5-sess
+        KD = lambda s, d: H("%s:%s" % (s, d))
+        return H, KD
+
+    def get_entity_digest(self, data, chal):
+        # XXX not implemented yet
+        return None
+
+
+class HTTPDigestAuthHandler(BaseHandler, AbstractDigestAuthHandler):
+    """An authentication protocol defined by RFC 2069
+
+    Digest authentication improves on basic authentication because it
+    does not transmit passwords in the clear.
+    """
+
+    auth_header = 'Authorization'
+    handler_order = 490  # before Basic auth
+
+    def http_error_401(self, req, fp, code, msg, headers):
+        host = urllib.parse.urlparse(req.get_full_url())[1]
+        retry = self.http_error_auth_reqed('www-authenticate',
+                                           host, req, headers)
+        self.reset_retry_count()
+        return retry
+
+
+class ProxyDigestAuthHandler(BaseHandler, AbstractDigestAuthHandler):
+
+    auth_header = 'Proxy-Authorization'
+    handler_order = 490  # before Basic auth
+
+    def http_error_407(self, req, fp, code, msg, headers):
+        host = req.get_host()
+        retry = self.http_error_auth_reqed('proxy-authenticate',
+                                           host, req, headers)
+        self.reset_retry_count()
+        return retry
+
+class AbstractHTTPHandler(BaseHandler):
+
+    def __init__(self, debuglevel=0):
+        self._debuglevel = debuglevel
+
+    def set_http_debuglevel(self, level):
+        self._debuglevel = level
+
+    def do_request_(self, request):
+        host = request.get_host()
+        if not host:
+            raise urllib.error.URLError('no host given')
+
+        if request.has_data():  # POST
+            data = request.get_data()
+            if not request.has_header('Content-type'):
+                request.add_unredirected_header(
+                    'Content-type',
+                    'application/x-www-form-urlencoded')
+            if not request.has_header('Content-length'):
+                request.add_unredirected_header(
+                    'Content-length', '%d' % len(data))
+
+        scheme, sel = urllib.parse.splittype(request.get_selector())
+        sel_host, sel_path = urllib.parse.splithost(sel)
+        if not request.has_header('Host'):
+            request.add_unredirected_header('Host', sel_host or host)
+        for name, value in self.parent.addheaders:
+            name = name.capitalize()
+            if not request.has_header(name):
+                request.add_unredirected_header(name, value)
+
+        return request
+
+    def do_open(self, http_class, req):
+        """Return an addinfourl object for the request, using http_class.
+
+        http_class must implement the HTTPConnection API from http.client.
+        The addinfourl return value is a file-like object.  It also
+        has methods and attributes including:
+            - info(): return a mimetools.Message object for the headers
+            - geturl(): return the original request URL
+            - code: HTTP status code
+        """
+        host = req.get_host()
+        if not host:
+            raise urllib.error.URLError('no host given')
+
+        h = http_class(host, timeout=req.timeout) # will parse host:port
+        headers = dict(req.headers)
+        headers.update(req.unredirected_hdrs)
+
+        # TODO(jhylton): Should this be redesigned to handle
+        # persistent connections?
+
+        # We want to make an HTTP/1.1 request, but the addinfourl
+        # class isn't prepared to deal with a persistent connection.
+        # It will try to read all remaining data from the socket,
+        # which will block while the server waits for the next request.
+        # So make sure the connection gets closed after the (only)
+        # request.
+        headers["Connection"] = "close"
+        headers = dict(
+            (name.title(), val) for name, val in headers.items())
+        try:
+            h.request(req.get_method(), req.get_selector(), req.data, headers)
+            r = h.getresponse()
+        except socket.error as err: # XXX what error?
+            raise urllib.error.URLError(err)
+
+        resp = urllib.response.addinfourl(r.fp, r.msg, req.get_full_url())
+        resp.code = r.status
+        resp.msg = r.reason
+        return resp
+
+
+class HTTPHandler(AbstractHTTPHandler):
+
+    def http_open(self, req):
+        return self.do_open(http.client.HTTPConnection, req)
+
+    http_request = AbstractHTTPHandler.do_request_
+
+if hasattr(http.client, 'HTTPSConnection'):
+    class HTTPSHandler(AbstractHTTPHandler):
+
+        def https_open(self, req):
+            return self.do_open(http.client.HTTPSConnection, req)
+
+        https_request = AbstractHTTPHandler.do_request_
+
+class HTTPCookieProcessor(BaseHandler):
+    def __init__(self, cookiejar=None):
+        import http.cookiejar
+        if cookiejar is None:
+            cookiejar = http.cookiejar.CookieJar()
+        self.cookiejar = cookiejar
+
+    def http_request(self, request):
+        self.cookiejar.add_cookie_header(request)
+        return request
+
+    def http_response(self, request, response):
+        self.cookiejar.extract_cookies(response, request)
+        return response
+
+    https_request = http_request
+    https_response = http_response
+
+class UnknownHandler(BaseHandler):
+    def unknown_open(self, req):
+        type = req.get_type()
+        raise urllib.error.URLError('unknown url type: %s' % type)
+
+def parse_keqv_list(l):
+    """Parse list of key=value strings where keys are not duplicated."""
+    parsed = {}
+    for elt in l:
+        k, v = elt.split('=', 1)
+        if v[0] == '"' and v[-1] == '"':
+            v = v[1:-1]
+        parsed[k] = v
+    return parsed
+
+def parse_http_list(s):
+    """Parse lists as described by RFC 2068 Section 2.
+
+    In particular, parse comma-separated lists where the elements of
+    the list may include quoted-strings.  A quoted-string could
+    contain a comma.  A non-quoted string could have quotes in the
+    middle.  Neither commas nor quotes count if they are escaped.
+    Only double-quotes count, not single-quotes.
+    """
+    res = []
+    part = ''
+
+    escape = quote = False
+    for cur in s:
+        if escape:
+            part += cur
+            escape = False
+            continue
+        if quote:
+            if cur == '\\':
+                escape = True
+                continue
+            elif cur == '"':
+                quote = False
+            part += cur
+            continue
+
+        if cur == ',':
+            res.append(part)
+            part = ''
+            continue
+
+        if cur == '"':
+            quote = True
+
+        part += cur
+
+    # append last part
+    if part:
+        res.append(part)
+
+    return [part.strip() for part in res]
+
+class FileHandler(BaseHandler):
+    # Use local file or FTP depending on form of URL
+    def file_open(self, req):
+        url = req.get_selector()
+        if url[:2] == '//' and url[2:3] != '/':
+            req.type = 'ftp'
+            return self.parent.open(req)
+        else:
+            return self.open_local_file(req)
+
+    # names for the localhost
+    names = None
+    def get_names(self):
+        if FileHandler.names is None:
+            try:
+                FileHandler.names = (socket.gethostbyname('localhost'),
+                                    socket.gethostbyname(socket.gethostname()))
+            except socket.gaierror:
+                FileHandler.names = (socket.gethostbyname('localhost'),)
+        return FileHandler.names
+
+    # not entirely sure what the rules are here
+    def open_local_file(self, req):
+        import email.utils
+        import mimetypes
+        host = req.get_host()
+        file = req.get_selector()
+        localfile = url2pathname(file)
+        try:
+            stats = os.stat(localfile)
+            size = stats.st_size
+            modified = email.utils.formatdate(stats.st_mtime, usegmt=True)
+            mtype = mimetypes.guess_type(file)[0]
+            headers = email.message_from_string(
+                'Content-type: %s\nContent-length: %d\nLast-modified: %s\n' %
+                (mtype or 'text/plain', size, modified))
+            if host:
+                host, port = urllib.parse.splitport(host)
+            if not host or \
+                (not port and _safe_gethostbyname(host) in self.get_names()):
+                return urllib.response.addinfourl(open(localfile, 'rb'),
+                                                  headers, 'file:'+file)
+        except OSError as msg:
+            # urllib2 users shouldn't expect OSErrors coming from urlopen()
+            raise urllib.error.URLError(msg)
+        raise urllib.error.URLError('file not on local host')
+
+def _safe_gethostbyname(host):
+    try:
+        return socket.gethostbyname(host)
+    except socket.gaierror:
+        return None
+
+class FTPHandler(BaseHandler):
+    def ftp_open(self, req):
+        import ftplib
+        import mimetypes
+        host = req.get_host()
+        if not host:
+            raise urllib.error.URLError('ftp error: no host given')
+        host, port = urllib.parse.splitport(host)
+        if port is None:
+            port = ftplib.FTP_PORT
+        else:
+            port = int(port)
+
+        # username/password handling
+        user, host = urllib.parse.splituser(host)
+        if user:
+            user, passwd = urllib.parse.splitpasswd(user)
+        else:
+            passwd = None
+        host = urllib.parse.unquote(host)
+        user = urllib.parse.unquote(user or '')
+        passwd = urllib.parse.unquote(passwd or '')
+
+        try:
+            host = socket.gethostbyname(host)
+        except socket.error as msg:
+            raise urllib.error.URLError(msg)
+        path, attrs = urllib.parse.splitattr(req.get_selector())
+        dirs = path.split('/')
+        dirs = list(map(urllib.parse.unquote, dirs))
+        dirs, file = dirs[:-1], dirs[-1]
+        if dirs and not dirs[0]:
+            dirs = dirs[1:]
+        try:
+            fw = self.connect_ftp(user, passwd, host, port, dirs, req.timeout)
+            type = file and 'I' or 'D'
+            for attr in attrs:
+                attr, value = urllib.parse.splitvalue(attr)
+                if attr.lower() == 'type' and \
+                   value in ('a', 'A', 'i', 'I', 'd', 'D'):
+                    type = value.upper()
+            fp, retrlen = fw.retrfile(file, type)
+            headers = ""
+            mtype = mimetypes.guess_type(req.get_full_url())[0]
+            if mtype:
+                headers += "Content-type: %s\n" % mtype
+            if retrlen is not None and retrlen >= 0:
+                headers += "Content-length: %d\n" % retrlen
+            headers = email.message_from_string(headers)
+            return urllib.response.addinfourl(fp, headers, req.get_full_url())
+        except ftplib.all_errors as msg:
+            exc = urllib.error.URLError('ftp error: %s' % msg)
+            raise exc.with_traceback(sys.exc_info()[2])
+
+    def connect_ftp(self, user, passwd, host, port, dirs, timeout):
+        fw = ftpwrapper(user, passwd, host, port, dirs, timeout)
+        return fw
+
+class CacheFTPHandler(FTPHandler):
+    # XXX would be nice to have pluggable cache strategies
+    # XXX this stuff is definitely not thread safe
+    def __init__(self):
+        self.cache = {}
+        self.timeout = {}
+        self.soonest = 0
+        self.delay = 60
+        self.max_conns = 16
+
+    def setTimeout(self, t):
+        self.delay = t
+
+    def setMaxConns(self, m):
+        self.max_conns = m
+
+    def connect_ftp(self, user, passwd, host, port, dirs, timeout):
+        key = user, host, port, '/'.join(dirs), timeout
+        if key in self.cache:
+            self.timeout[key] = time.time() + self.delay
+        else:
+            self.cache[key] = ftpwrapper(user, passwd, host, port,
+                                         dirs, timeout)
+            self.timeout[key] = time.time() + self.delay
+        self.check_cache()
+        return self.cache[key]
+
+    def check_cache(self):
+        # first check for old ones
+        t = time.time()
+        if self.soonest <= t:
+            for k, v in list(self.timeout.items()):
+                if v < t:
+                    self.cache[k].close()
+                    del self.cache[k]
+                    del self.timeout[k]
+        self.soonest = min(list(self.timeout.values()))
+
+        # then check the size
+        if len(self.cache) == self.max_conns:
+            for k, v in list(self.timeout.items()):
+                if v == self.soonest:
+                    del self.cache[k]
+                    del self.timeout[k]
+                    break
+            self.soonest = min(list(self.timeout.values()))
+
+# Code move from the old urllib module
+
+MAXFTPCACHE = 10        # Trim the ftp cache beyond this size
+
+# Helper for non-unix systems
+if os.name == 'mac':
+    from macurl2path import url2pathname, pathname2url
+elif os.name == 'nt':
+    from nturl2path import url2pathname, pathname2url
+else:
+    def url2pathname(pathname):
+        """OS-specific conversion from a relative URL of the 'file' scheme
+        to a file system path; not recommended for general use."""
+        return urllib.parse.unquote(pathname)
+
+    def pathname2url(pathname):
+        """OS-specific conversion from a file system path to a relative URL
+        of the 'file' scheme; not recommended for general use."""
+        return urllib.parse.quote(pathname)
+
+# This really consists of two pieces:
+# (1) a class which handles opening of all sorts of URLs
+#     (plus assorted utilities etc.)
+# (2) a set of functions for parsing URLs
+# XXX Should these be separated out into different modules?
+
+
+ftpcache = {}
+class URLopener:
+    """Class to open URLs.
+    This is a class rather than just a subroutine because we may need
+    more than one set of global protocol-specific options.
+    Note -- this is a base class for those who don't want the
+    automatic handling of errors type 302 (relocated) and 401
+    (authorization needed)."""
+
+    __tempfiles = None
+
+    version = "Python-urllib/%s" % __version__
+
+    # Constructor
+    def __init__(self, proxies=None, **x509):
+        if proxies is None:
+            proxies = getproxies()
+        assert hasattr(proxies, 'keys'), "proxies must be a mapping"
+        self.proxies = proxies
+        self.key_file = x509.get('key_file')
+        self.cert_file = x509.get('cert_file')
+        self.addheaders = [('User-Agent', self.version)]
+        self.__tempfiles = []
+        self.__unlink = os.unlink # See cleanup()
+        self.tempcache = None
+        # Undocumented feature: if you assign {} to tempcache,
+        # it is used to cache files retrieved with
+        # self.retrieve().  This is not enabled by default
+        # since it does not work for changing documents (and I
+        # haven't got the logic to check expiration headers
+        # yet).
+        self.ftpcache = ftpcache
+        # Undocumented feature: you can use a different
+        # ftp cache by assigning to the .ftpcache member;
+        # in case you want logically independent URL openers
+        # XXX This is not threadsafe.  Bah.
+
+    def __del__(self):
+        self.close()
+
+    def close(self):
+        self.cleanup()
+
+    def cleanup(self):
+        # This code sometimes runs when the rest of this module
+        # has already been deleted, so it can't use any globals
+        # or import anything.
+        if self.__tempfiles:
+            for file in self.__tempfiles:
+                try:
+                    self.__unlink(file)
+                except OSError:
+                    pass
+            del self.__tempfiles[:]
+        if self.tempcache:
+            self.tempcache.clear()
+
+    def addheader(self, *args):
+        """Add a header to be used by the HTTP interface only
+        e.g. u.addheader('Accept', 'sound/basic')"""
+        self.addheaders.append(args)
+
+    # External interface
+    def open(self, fullurl, data=None):
+        """Use URLopener().open(file) instead of open(file, 'r')."""
+        fullurl = urllib.parse.unwrap(urllib.parse.toBytes(fullurl))
+        if self.tempcache and fullurl in self.tempcache:
+            filename, headers = self.tempcache[fullurl]
+            fp = open(filename, 'rb')
+            return urllib.response.addinfourl(fp, headers, fullurl)
+        urltype, url = urllib.parse.splittype(fullurl)
+        if not urltype:
+            urltype = 'file'
+        if urltype in self.proxies:
+            proxy = self.proxies[urltype]
+            urltype, proxyhost = urllib.parse.splittype(proxy)
+            host, selector = urllib.parse.splithost(proxyhost)
+            url = (host, fullurl) # Signal special case to open_*()
+        else:
+            proxy = None
+        name = 'open_' + urltype
+        self.type = urltype
+        name = name.replace('-', '_')
+        if not hasattr(self, name):
+            if proxy:
+                return self.open_unknown_proxy(proxy, fullurl, data)
+            else:
+                return self.open_unknown(fullurl, data)
+        try:
+            if data is None:
+                return getattr(self, name)(url)
+            else:
+                return getattr(self, name)(url, data)
+        except socket.error as msg:
+            raise IOError('socket error', msg).with_traceback(sys.exc_info()[2])
+
+    def open_unknown(self, fullurl, data=None):
+        """Overridable interface to open unknown URL type."""
+        type, url = urllib.parse.splittype(fullurl)
+        raise IOError('url error', 'unknown url type', type)
+
+    def open_unknown_proxy(self, proxy, fullurl, data=None):
+        """Overridable interface to open unknown URL type."""
+        type, url = urllib.parse.splittype(fullurl)
+        raise IOError('url error', 'invalid proxy for %s' % type, proxy)
+
+    # External interface
+    def retrieve(self, url, filename=None, reporthook=None, data=None):
+        """retrieve(url) returns (filename, headers) for a local object
+        or (tempfilename, headers) for a remote object."""
+        url = urllib.parse.unwrap(urllib.parse.toBytes(url))
+        if self.tempcache and url in self.tempcache:
+            return self.tempcache[url]
+        type, url1 = urllib.parse.splittype(url)
+        if filename is None and (not type or type == 'file'):
+            try:
+                fp = self.open_local_file(url1)
+                hdrs = fp.info()
+                del fp
+                return url2pathname(urllib.parse.splithost(url1)[1]), hdrs
+            except IOError as msg:
+                pass
+        fp = self.open(url, data)
+        headers = fp.info()
+        if filename:
+            tfp = open(filename, 'wb')
+        else:
+            import tempfile
+            garbage, path = urllib.parse.splittype(url)
+            garbage, path = urllib.parse.splithost(path or "")
+            path, garbage = urllib.parse.splitquery(path or "")
+            path, garbage = urllib.parse.splitattr(path or "")
+            suffix = os.path.splitext(path)[1]
+            (fd, filename) = tempfile.mkstemp(suffix)
+            self.__tempfiles.append(filename)
+            tfp = os.fdopen(fd, 'wb')
+        result = filename, headers
+        if self.tempcache is not None:
+            self.tempcache[url] = result
+        bs = 1024*8
+        size = -1
+        read = 0
+        blocknum = 0
+        if reporthook:
+            if "content-length" in headers:
+                size = int(headers["Content-Length"])
+            reporthook(blocknum, bs, size)
+        while 1:
+            block = fp.read(bs)
+            if not block:
+                break
+            read += len(block)
+            tfp.write(block)
+            blocknum += 1
+            if reporthook:
+                reporthook(blocknum, bs, size)
+        fp.close()
+        tfp.close()
+        del fp
+        del tfp
+
+        # raise exception if actual size does not match content-length header
+        if size >= 0 and read < size:
+            raise urllib.error.ContentTooShortError(
+                "retrieval incomplete: got only %i out of %i bytes"
+                % (read, size), result)
+
+        return result
+
+    # Each method named open_<type> knows how to open that type of URL
+
+    def _open_generic_http(self, connection_factory, url, data):
+        """Make an HTTP connection using connection_class.
+
+        This is an internal method that should be called from
+        open_http() or open_https().
+
+        Arguments:
+        - connection_factory should take a host name and return an
+          HTTPConnection instance.
+        - url is the url to retrieval or a host, relative-path pair.
+        - data is payload for a POST request or None.
+        """
+
+        user_passwd = None
+        proxy_passwd= None
+        if isinstance(url, str):
+            host, selector = urllib.parse.splithost(url)
+            if host:
+                user_passwd, host = urllib.parse.splituser(host)
+                host = urllib.parse.unquote(host)
+            realhost = host
+        else:
+            host, selector = url
+            # check whether the proxy contains authorization information
+            proxy_passwd, host = urllib.parse.splituser(host)
+            # now we proceed with the url we want to obtain
+            urltype, rest = urllib.parse.splittype(selector)
+            url = rest
+            user_passwd = None
+            if urltype.lower() != 'http':
+                realhost = None
+            else:
+                realhost, rest = urllib.parse.splithost(rest)
+                if realhost:
+                    user_passwd, realhost = urllib.parse.splituser(realhost)
+                if user_passwd:
+                    selector = "%s://%s%s" % (urltype, realhost, rest)
+                if proxy_bypass(realhost):
+                    host = realhost
+
+            #print "proxy via http:", host, selector
+        if not host: raise IOError('http error', 'no host given')
+
+        if proxy_passwd:
+            import base64
+            proxy_auth = base64.b64encode(proxy_passwd).strip()
+        else:
+            proxy_auth = None
+
+        if user_passwd:
+            import base64
+            auth = base64.b64encode(user_passwd).strip()
+        else:
+            auth = None
+        http_conn = connection_factory(host)
+        # XXX We should fix urllib so that it works with HTTP/1.1.
+        http_conn._http_vsn = 10
+        http_conn._http_vsn_str = "HTTP/1.0"
+
+        headers = {}
+        if proxy_auth:
+            headers["Proxy-Authorization"] = "Basic %s" % proxy_auth
+        if auth:
+            headers["Authorization"] =  "Basic %s" % auth
+        if realhost:
+            headers["Host"] = realhost
+        for header, value in self.addheaders:
+            headers[header] = value
+
+        if data is not None:
+            headers["Content-Type"] = "application/x-www-form-urlencoded"
+            http_conn.request("POST", selector, data, headers)
+        else:
+            http_conn.request("GET", selector, headers=headers)
+
+        try:
+            response = http_conn.getresponse()
+        except http.client.BadStatusLine:
+            # something went wrong with the HTTP status line
+            raise urllib.error.URLError("http protocol error: bad status line")
+
+        # According to RFC 2616, "2xx" code indicates that the client's
+        # request was successfully received, understood, and accepted.
+        if 200 <= response.status < 300:
+            return urllib.response.addinfourl(response.fp, response.msg,
+                                              "http:" + url,
+                                              response.status)
+        else:
+            return self.http_error(
+                url, response.fp,
+                response.status, response.reason, response.msg, data)
+
+    def open_http(self, url, data=None):
+        """Use HTTP protocol."""
+        return self._open_generic_http(http.client.HTTPConnection, url, data)
+
+    def http_error(self, url, fp, errcode, errmsg, headers, data=None):
+        """Handle http errors.
+
+        Derived class can override this, or provide specific handlers
+        named http_error_DDD where DDD is the 3-digit error code."""
+        # First check if there's a specific handler for this error
+        name = 'http_error_%d' % errcode
+        if hasattr(self, name):
+            method = getattr(self, name)
+            if data is None:
+                result = method(url, fp, errcode, errmsg, headers)
+            else:
+                result = method(url, fp, errcode, errmsg, headers, data)
+            if result: return result
+        return self.http_error_default(url, fp, errcode, errmsg, headers)
+
+    def http_error_default(self, url, fp, errcode, errmsg, headers):
+        """Default error handler: close the connection and raise IOError."""
+        void = fp.read()
+        fp.close()
+        raise urllib.error.HTTPError(url, errcode, errmsg, headers, None)
+
+    if _have_ssl:
+        def _https_connection(self, host):
+            return http.client.HTTPSConnection(host,
+                                           key_file=self.key_file,
+                                           cert_file=self.cert_file)
+
+        def open_https(self, url, data=None):
+            """Use HTTPS protocol."""
+            return self._open_generic_http(self._https_connection, url, data)
+
+    def open_file(self, url):
+        """Use local file or FTP depending on form of URL."""
+        if not isinstance(url, str):
+            raise URLError('file error', 'proxy support for file protocol currently not implemented')
+        if url[:2] == '//' and url[2:3] != '/' and url[2:12].lower() != 'localhost/':
+            return self.open_ftp(url)
+        else:
+            return self.open_local_file(url)
+
+    def open_local_file(self, url):
+        """Use local file."""
+        import mimetypes, email.utils
+        from io import StringIO
+        host, file = urllib.parse.splithost(url)
+        localname = url2pathname(file)
+        try:
+            stats = os.stat(localname)
+        except OSError as e:
+            raise URLError(e.errno, e.strerror, e.filename)
+        size = stats.st_size
+        modified = email.utils.formatdate(stats.st_mtime, usegmt=True)
+        mtype = mimetypes.guess_type(url)[0]
+        headers = email.message_from_string(
+            'Content-Type: %s\nContent-Length: %d\nLast-modified: %s\n' %
+            (mtype or 'text/plain', size, modified))
+        if not host:
+            urlfile = file
+            if file[:1] == '/':
+                urlfile = 'file://' + file
+            return urllib.response.addinfourl(open(localname, 'rb'),
+                                              headers, urlfile)
+        host, port = urllib.parse.splitport(host)
+        if (not port
+           and socket.gethostbyname(host) in (localhost(), thishost())):
+            urlfile = file
+            if file[:1] == '/':
+                urlfile = 'file://' + file
+            return urllib.response.addinfourl(open(localname, 'rb'),
+                                              headers, urlfile)
+        raise URLError('local file error', 'not on local host')
+
+    def open_ftp(self, url):
+        """Use FTP protocol."""
+        if not isinstance(url, str):
+            raise URLError('ftp error', 'proxy support for ftp protocol currently not implemented')
+        import mimetypes
+        from io import StringIO
+        host, path = urllib.parse.splithost(url)
+        if not host: raise URLError('ftp error', 'no host given')
+        host, port = urllib.parse.splitport(host)
+        user, host = urllib.parse.splituser(host)
+        if user: user, passwd = urllib.parse.splitpasswd(user)
+        else: passwd = None
+        host = urllib.parse.unquote(host)
+        user = urllib.parse.unquote(user or '')
+        passwd = urllib.parse.unquote(passwd or '')
+        host = socket.gethostbyname(host)
+        if not port:
+            import ftplib
+            port = ftplib.FTP_PORT
+        else:
+            port = int(port)
+        path, attrs = urllib.parse.splitattr(path)
+        path = urllib.parse.unquote(path)
+        dirs = path.split('/')
+        dirs, file = dirs[:-1], dirs[-1]
+        if dirs and not dirs[0]: dirs = dirs[1:]
+        if dirs and not dirs[0]: dirs[0] = '/'
+        key = user, host, port, '/'.join(dirs)
+        # XXX thread unsafe!
+        if len(self.ftpcache) > MAXFTPCACHE:
+            # Prune the cache, rather arbitrarily
+            for k in self.ftpcache.keys():
+                if k != key:
+                    v = self.ftpcache[k]
+                    del self.ftpcache[k]
+                    v.close()
+        try:
+            if not key in self.ftpcache:
+                self.ftpcache[key] = \
+                    ftpwrapper(user, passwd, host, port, dirs)
+            if not file: type = 'D'
+            else: type = 'I'
+            for attr in attrs:
+                attr, value = urllib.parse.splitvalue(attr)
+                if attr.lower() == 'type' and \
+                   value in ('a', 'A', 'i', 'I', 'd', 'D'):
+                    type = value.upper()
+            (fp, retrlen) = self.ftpcache[key].retrfile(file, type)
+            mtype = mimetypes.guess_type("ftp:" + url)[0]
+            headers = ""
+            if mtype:
+                headers += "Content-Type: %s\n" % mtype
+            if retrlen is not None and retrlen >= 0:
+                headers += "Content-Length: %d\n" % retrlen
+            headers = email.message_from_string(headers)
+            return urllib.response.addinfourl(fp, headers, "ftp:" + url)
+        except ftperrors() as msg:
+            raise URLError('ftp error', msg).with_traceback(sys.exc_info()[2])
+
+    def open_data(self, url, data=None):
+        """Use "data" URL."""
+        if not isinstance(url, str):
+            raise URLError('data error', 'proxy support for data protocol currently not implemented')
+        # ignore POSTed data
+        #
+        # syntax of data URLs:
+        # dataurl   := "data:" [ mediatype ] [ ";base64" ] "," data
+        # mediatype := [ type "/" subtype ] *( ";" parameter )
+        # data      := *urlchar
+        # parameter := attribute "=" value
+        try:
+            [type, data] = url.split(',', 1)
+        except ValueError:
+            raise IOError('data error', 'bad data URL')
+        if not type:
+            type = 'text/plain;charset=US-ASCII'
+        semi = type.rfind(';')
+        if semi >= 0 and '=' not in type[semi:]:
+            encoding = type[semi+1:]
+            type = type[:semi]
+        else:
+            encoding = ''
+        msg = []
+        msg.append('Date: %s'%time.strftime('%a, %d %b %Y %T GMT',
+                                            time.gmtime(time.time())))
+        msg.append('Content-type: %s' % type)
+        if encoding == 'base64':
+            import base64
+            data = base64.decodestring(data)
+        else:
+            data = urllib.parse.unquote(data)
+        msg.append('Content-Length: %d' % len(data))
+        msg.append('')
+        msg.append(data)
+        msg = '\n'.join(msg)
+        headers = mimetools.message_from_string(msg)
+        #f.fileno = None     # needed for addinfourl
+        return urllib.response.addinfourl(f, headers, url)
+
+
+class FancyURLopener(URLopener):
+    """Derived class with handlers for errors we can handle (perhaps)."""
+
+    def __init__(self, *args, **kwargs):
+        URLopener.__init__(self, *args, **kwargs)
+        self.auth_cache = {}
+        self.tries = 0
+        self.maxtries = 10
+
+    def http_error_default(self, url, fp, errcode, errmsg, headers):
+        """Default error handling -- don't raise an exception."""
+        return urllib.response.addinfourl(fp, headers, "http:" + url, errcode)
+
+    def http_error_302(self, url, fp, errcode, errmsg, headers, data=None):
+        """Error 302 -- relocated (temporarily)."""
+        self.tries += 1
+        if self.maxtries and self.tries >= self.maxtries:
+            if hasattr(self, "http_error_500"):
+                meth = self.http_error_500
+            else:
+                meth = self.http_error_default
+            self.tries = 0
+            return meth(url, fp, 500,
+                        "Internal Server Error: Redirect Recursion", headers)
+        result = self.redirect_internal(url, fp, errcode, errmsg, headers,
+                                        data)
+        self.tries = 0
+        return result
+
+    def redirect_internal(self, url, fp, errcode, errmsg, headers, data):
+        if 'location' in headers:
+            newurl = headers['location']
+        elif 'uri' in headers:
+            newurl = headers['uri']
+        else:
+            return
+        void = fp.read()
+        fp.close()
+        # In case the server sent a relative URL, join with original:
+        newurl = basejoin(self.type + ":" + url, newurl)
+        return self.open(newurl)
+
+    def http_error_301(self, url, fp, errcode, errmsg, headers, data=None):
+        """Error 301 -- also relocated (permanently)."""
+        return self.http_error_302(url, fp, errcode, errmsg, headers, data)
+
+    def http_error_303(self, url, fp, errcode, errmsg, headers, data=None):
+        """Error 303 -- also relocated (essentially identical to 302)."""
+        return self.http_error_302(url, fp, errcode, errmsg, headers, data)
+
+    def http_error_307(self, url, fp, errcode, errmsg, headers, data=None):
+        """Error 307 -- relocated, but turn POST into error."""
+        if data is None:
+            return self.http_error_302(url, fp, errcode, errmsg, headers, data)
+        else:
+            return self.http_error_default(url, fp, errcode, errmsg, headers)
+
+    def http_error_401(self, url, fp, errcode, errmsg, headers, data=None):
+        """Error 401 -- authentication required.
+        This function supports Basic authentication only."""
+        if not 'www-authenticate' in headers:
+            URLopener.http_error_default(self, url, fp,
+                                         errcode, errmsg, headers)
+        stuff = headers['www-authenticate']
+        import re
+        match = re.match('[ \t]*([^ \t]+)[ \t]+realm="([^"]*)"', stuff)
+        if not match:
+            URLopener.http_error_default(self, url, fp,
+                                         errcode, errmsg, headers)
+        scheme, realm = match.groups()
+        if scheme.lower() != 'basic':
+            URLopener.http_error_default(self, url, fp,
+                                         errcode, errmsg, headers)
+        name = 'retry_' + self.type + '_basic_auth'
+        if data is None:
+            return getattr(self,name)(url, realm)
+        else:
+            return getattr(self,name)(url, realm, data)
+
+    def http_error_407(self, url, fp, errcode, errmsg, headers, data=None):
+        """Error 407 -- proxy authentication required.
+        This function supports Basic authentication only."""
+        if not 'proxy-authenticate' in headers:
+            URLopener.http_error_default(self, url, fp,
+                                         errcode, errmsg, headers)
+        stuff = headers['proxy-authenticate']
+        import re
+        match = re.match('[ \t]*([^ \t]+)[ \t]+realm="([^"]*)"', stuff)
+        if not match:
+            URLopener.http_error_default(self, url, fp,
+                                         errcode, errmsg, headers)
+        scheme, realm = match.groups()
+        if scheme.lower() != 'basic':
+            URLopener.http_error_default(self, url, fp,
+                                         errcode, errmsg, headers)
+        name = 'retry_proxy_' + self.type + '_basic_auth'
+        if data is None:
+            return getattr(self,name)(url, realm)
+        else:
+            return getattr(self,name)(url, realm, data)
+
+    def retry_proxy_http_basic_auth(self, url, realm, data=None):
+        host, selector = urllib.parse.splithost(url)
+        newurl = 'http://' + host + selector
+        proxy = self.proxies['http']
+        urltype, proxyhost = urllib.parse.splittype(proxy)
+        proxyhost, proxyselector = urllib.parse.splithost(proxyhost)
+        i = proxyhost.find('@') + 1
+        proxyhost = proxyhost[i:]
+        user, passwd = self.get_user_passwd(proxyhost, realm, i)
+        if not (user or passwd): return None
+        proxyhost = "%s:%s@%s" % (urllib.parse.quote(user, safe=''),
+                                  quote(passwd, safe=''), proxyhost)
+        self.proxies['http'] = 'http://' + proxyhost + proxyselector
+        if data is None:
+            return self.open(newurl)
+        else:
+            return self.open(newurl, data)
+
+    def retry_proxy_https_basic_auth(self, url, realm, data=None):
+        host, selector = urllib.parse.splithost(url)
+        newurl = 'https://' + host + selector
+        proxy = self.proxies['https']
+        urltype, proxyhost = urllib.parse.splittype(proxy)
+        proxyhost, proxyselector = urllib.parse.splithost(proxyhost)
+        i = proxyhost.find('@') + 1
+        proxyhost = proxyhost[i:]
+        user, passwd = self.get_user_passwd(proxyhost, realm, i)
+        if not (user or passwd): return None
+        proxyhost = "%s:%s@%s" % (urllib.parse.quote(user, safe=''),
+                                  quote(passwd, safe=''), proxyhost)
+        self.proxies['https'] = 'https://' + proxyhost + proxyselector
+        if data is None:
+            return self.open(newurl)
+        else:
+            return self.open(newurl, data)
+
+    def retry_http_basic_auth(self, url, realm, data=None):
+        host, selector = urllib.parse.splithost(url)
+        i = host.find('@') + 1
+        host = host[i:]
+        user, passwd = self.get_user_passwd(host, realm, i)
+        if not (user or passwd): return None
+        host = "%s:%s@%s" % (urllib.parse.quote(user, safe=''),
+                             quote(passwd, safe=''), host)
+        newurl = 'http://' + host + selector
+        if data is None:
+            return self.open(newurl)
+        else:
+            return self.open(newurl, data)
+
+    def retry_https_basic_auth(self, url, realm, data=None):
+        host, selector = urllib.parse.splithost(url)
+        i = host.find('@') + 1
+        host = host[i:]
+        user, passwd = self.get_user_passwd(host, realm, i)
+        if not (user or passwd): return None
+        host = "%s:%s@%s" % (urllib.parse.quote(user, safe=''),
+                             quote(passwd, safe=''), host)
+        newurl = 'https://' + host + selector
+        if data is None:
+            return self.open(newurl)
+        else:
+            return self.open(newurl, data)
+
+    def get_user_passwd(self, host, realm, clear_cache = 0):
+        key = realm + '@' + host.lower()
+        if key in self.auth_cache:
+            if clear_cache:
+                del self.auth_cache[key]
+            else:
+                return self.auth_cache[key]
+        user, passwd = self.prompt_user_passwd(host, realm)
+        if user or passwd: self.auth_cache[key] = (user, passwd)
+        return user, passwd
+
+    def prompt_user_passwd(self, host, realm):
+        """Override this in a GUI environment!"""
+        import getpass
+        try:
+            user = input("Enter username for %s at %s: " % (realm, host))
+            passwd = getpass.getpass("Enter password for %s in %s at %s: " %
+                (user, realm, host))
+            return user, passwd
+        except KeyboardInterrupt:
+            print()
+            return None, None
+
+
+# Utility functions
+
+_localhost = None
+def localhost():
+    """Return the IP address of the magic hostname 'localhost'."""
+    global _localhost
+    if _localhost is None:
+        _localhost = socket.gethostbyname('localhost')
+    return _localhost
+
+_thishost = None
+def thishost():
+    """Return the IP address of the current host."""
+    global _thishost
+    if _thishost is None:
+        _thishost = socket.gethostbyname(socket.gethostname())
+    return _thishost
+
+_ftperrors = None
+def ftperrors():
+    """Return the set of errors raised by the FTP class."""
+    global _ftperrors
+    if _ftperrors is None:
+        import ftplib
+        _ftperrors = ftplib.all_errors
+    return _ftperrors
+
+_noheaders = None
+def noheaders():
+    """Return an empty mimetools.Message object."""
+    global _noheaders
+    if _noheaders is None:
+        _noheaders = mimetools.message_from_string("")
+    return _noheaders
+
+
+# Utility classes
+
+class ftpwrapper:
+    """Class used by open_ftp() for cache of open FTP connections."""
+
+    def __init__(self, user, passwd, host, port, dirs, timeout=None):
+        self.user = user
+        self.passwd = passwd
+        self.host = host
+        self.port = port
+        self.dirs = dirs
+        self.timeout = timeout
+        self.init()
+
+    def init(self):
+        import ftplib
+        self.busy = 0
+        self.ftp = ftplib.FTP()
+        self.ftp.connect(self.host, self.port, self.timeout)
+        self.ftp.login(self.user, self.passwd)
+        for dir in self.dirs:
+            self.ftp.cwd(dir)
+
+    def retrfile(self, file, type):
+        import ftplib
+        self.endtransfer()
+        if type in ('d', 'D'): cmd = 'TYPE A'; isdir = 1
+        else: cmd = 'TYPE ' + type; isdir = 0
+        try:
+            self.ftp.voidcmd(cmd)
+        except ftplib.all_errors:
+            self.init()
+            self.ftp.voidcmd(cmd)
+        conn = None
+        if file and not isdir:
+            # Try to retrieve as a file
+            try:
+                cmd = 'RETR ' + file
+                conn = self.ftp.ntransfercmd(cmd)
+            except ftplib.error_perm as reason:
+                if str(reason)[:3] != '550':
+                    raise urllib.error.URLError('ftp error', reason).with_traceback(sys.exc_info()[2])
+        if not conn:
+            # Set transfer mode to ASCII!
+            self.ftp.voidcmd('TYPE A')
+            # Try a directory listing. Verify that directory exists.
+            if file:
+                pwd = self.ftp.pwd()
+                try:
+                    try:
+                        self.ftp.cwd(file)
+                    except ftplib.error_perm as reason:
+                        raise urllib.error.URLError('ftp error', reason) from reason
+                finally:
+                    self.ftp.cwd(pwd)
+                cmd = 'LIST ' + file
+            else:
+                cmd = 'LIST'
+            conn = self.ftp.ntransfercmd(cmd)
+        self.busy = 1
+        # Pass back both a suitably decorated object and a retrieval length
+        return (urllib.response.addclosehook(conn[0].makefile('rb'),
+                                             self.endtransfer), conn[1])
+    def endtransfer(self):
+        if not self.busy:
+            return
+        self.busy = 0
+        try:
+            self.ftp.voidresp()
+        except ftperrors():
+            pass
+
+    def close(self):
+        self.endtransfer()
+        try:
+            self.ftp.close()
+        except ftperrors():
+            pass
+
+# Proxy handling
+def getproxies_environment():
+    """Return a dictionary of scheme -> proxy server URL mappings.
+
+    Scan the environment for variables named <scheme>_proxy;
+    this seems to be the standard convention.  If you need a
+    different way, you can pass a proxies dictionary to the
+    [Fancy]URLopener constructor.
+
+    """
+    proxies = {}
+    for name, value in os.environ.items():
+        name = name.lower()
+        if name == 'no_proxy':
+            # handled in proxy_bypass_environment
+            continue
+        if value and name[-6:] == '_proxy':
+            proxies[name[:-6]] = value
+    return proxies
+
+def proxy_bypass_environment(host):
+    """Test if proxies should not be used for a particular host.
+
+    Checks the environment for a variable named no_proxy, which should
+    be a list of DNS suffixes separated by commas, or '*' for all hosts.
+    """
+    no_proxy = os.environ.get('no_proxy', '') or os.environ.get('NO_PROXY', '')
+    # '*' is special case for always bypass
+    if no_proxy == '*':
+        return 1
+    # strip port off host
+    hostonly, port = urllib.parse.splitport(host)
+    # check if the host ends with any of the DNS suffixes
+    for name in no_proxy.split(','):
+        if name and (hostonly.endswith(name) or host.endswith(name)):
+            return 1
+    # otherwise, don't bypass
+    return 0
+
+
+if sys.platform == 'darwin':
+    def getproxies_internetconfig():
+        """Return a dictionary of scheme -> proxy server URL mappings.
+
+        By convention the mac uses Internet Config to store
+        proxies.  An HTTP proxy, for instance, is stored under
+        the HttpProxy key.
+
+        """
+        try:
+            import ic
+        except ImportError:
+            return {}
+
+        try:
+            config = ic.IC()
+        except ic.error:
+            return {}
+        proxies = {}
+        # HTTP:
+        if 'UseHTTPProxy' in config and config['UseHTTPProxy']:
+            try:
+                value = config['HTTPProxyHost']
+            except ic.error:
+                pass
+            else:
+                proxies['http'] = 'http://%s' % value
+        # FTP: XXX To be done.
+        # Gopher: XXX To be done.
+        return proxies
+
+    def proxy_bypass(host):
+        if getproxies_environment():
+            return proxy_bypass_environment(host)
+        else:
+            return 0
+
+    def getproxies():
+        return getproxies_environment() or getproxies_internetconfig()
+
+elif os.name == 'nt':
+    def getproxies_registry():
+        """Return a dictionary of scheme -> proxy server URL mappings.
+
+        Win32 uses the registry to store proxies.
+
+        """
+        proxies = {}
+        try:
+            import _winreg
+        except ImportError:
+            # Std module, so should be around - but you never know!
+            return proxies
+        try:
+            internetSettings = _winreg.OpenKey(_winreg.HKEY_CURRENT_USER,
+                r'Software\Microsoft\Windows\CurrentVersion\Internet Settings')
+            proxyEnable = _winreg.QueryValueEx(internetSettings,
+                                               'ProxyEnable')[0]
+            if proxyEnable:
+                # Returned as Unicode but problems if not converted to ASCII
+                proxyServer = str(_winreg.QueryValueEx(internetSettings,
+                                                       'ProxyServer')[0])
+                if '=' in proxyServer:
+                    # Per-protocol settings
+                    for p in proxyServer.split(';'):
+                        protocol, address = p.split('=', 1)
+                        # See if address has a type:// prefix
+                        import re
+                        if not re.match('^([^/:]+)://', address):
+                            address = '%s://%s' % (protocol, address)
+                        proxies[protocol] = address
+                else:
+                    # Use one setting for all protocols
+                    if proxyServer[:5] == 'http:':
+                        proxies['http'] = proxyServer
+                    else:
+                        proxies['http'] = 'http://%s' % proxyServer
+                        proxies['ftp'] = 'ftp://%s' % proxyServer
+            internetSettings.Close()
+        except (WindowsError, ValueError, TypeError):
+            # Either registry key not found etc, or the value in an
+            # unexpected format.
+            # proxies already set up to be empty so nothing to do
+            pass
+        return proxies
+
+    def getproxies():
+        """Return a dictionary of scheme -> proxy server URL mappings.
+
+        Returns settings gathered from the environment, if specified,
+        or the registry.
+
+        """
+        return getproxies_environment() or getproxies_registry()
+
+    def proxy_bypass_registry(host):
+        try:
+            import _winreg
+            import re
+        except ImportError:
+            # Std modules, so should be around - but you never know!
+            return 0
+        try:
+            internetSettings = _winreg.OpenKey(_winreg.HKEY_CURRENT_USER,
+                r'Software\Microsoft\Windows\CurrentVersion\Internet Settings')
+            proxyEnable = _winreg.QueryValueEx(internetSettings,
+                                               'ProxyEnable')[0]
+            proxyOverride = str(_winreg.QueryValueEx(internetSettings,
+                                                     'ProxyOverride')[0])
+            # ^^^^ Returned as Unicode but problems if not converted to ASCII
+        except WindowsError:
+            return 0
+        if not proxyEnable or not proxyOverride:
+            return 0
+        # try to make a host list from name and IP address.
+        rawHost, port = urllib.parse.splitport(host)
+        host = [rawHost]
+        try:
+            addr = socket.gethostbyname(rawHost)
+            if addr != rawHost:
+                host.append(addr)
+        except socket.error:
+            pass
+        try:
+            fqdn = socket.getfqdn(rawHost)
+            if fqdn != rawHost:
+                host.append(fqdn)
+        except socket.error:
+            pass
+        # make a check value list from the registry entry: replace the
+        # '<local>' string by the localhost entry and the corresponding
+        # canonical entry.
+        proxyOverride = proxyOverride.split(';')
+        i = 0
+        while i < len(proxyOverride):
+            if proxyOverride[i] == '<local>':
+                proxyOverride[i:i+1] = ['localhost',
+                                        '127.0.0.1',
+                                        socket.gethostname(),
+                                        socket.gethostbyname(
+                                            socket.gethostname())]
+            i += 1
+        # print proxyOverride
+        # now check if we match one of the registry values.
+        for test in proxyOverride:
+            test = test.replace(".", r"\.")     # mask dots
+            test = test.replace("*", r".*")     # change glob sequence
+            test = test.replace("?", r".")      # change glob char
+            for val in host:
+                # print "%s <--> %s" %( test, val )
+                if re.match(test, val, re.I):
+                    return 1
+        return 0
+
+    def proxy_bypass(host):
+        """Return a dictionary of scheme -> proxy server URL mappings.
+
+        Returns settings gathered from the environment, if specified,
+        or the registry.
+
+        """
+        if getproxies_environment():
+            return proxy_bypass_environment(host)
+        else:
+            return proxy_bypass_registry(host)
+
+else:
+    # By default use environment variables
+    getproxies = getproxies_environment
+    proxy_bypass = proxy_bypass_environment
diff --git a/Lib/urllib/response.py b/Lib/urllib/response.py
new file mode 100644
index 0000000000..1352622e31
--- /dev/null
+++ b/Lib/urllib/response.py
@@ -0,0 +1,83 @@
+"""Response classes used by urllib.
+
+The base class, addbase, defines a minimal file-like interface,
+including read() and readline().  The typical response object is an
+addinfourl instance, which defines an info() method that returns
+headers and a geturl() method that returns the url.
+"""
+
+class addbase(object):
+    """Base class for addinfo and addclosehook."""
+
+    # XXX Add a method to expose the timeout on the underlying socket?
+
+    def __init__(self, fp):
+        # TODO(jhylton): Is there a better way to delegate using io?
+        self.fp = fp
+        self.read = self.fp.read
+        self.readline = self.fp.readline
+        # TODO(jhylton): Make sure an object with readlines() is also iterable
+        if hasattr(self.fp, "readlines"): self.readlines = self.fp.readlines
+        if hasattr(self.fp, "fileno"):
+            self.fileno = self.fp.fileno
+        else:
+            self.fileno = lambda: None
+        if hasattr(self.fp, "__iter__"):
+            self.__iter__ = self.fp.__iter__
+            if hasattr(self.fp, "__next__"):
+                self.__next__ = self.fp.__next__
+
+    def __repr__(self):
+        return '<%s at %r whose fp = %r>' % (self.__class__.__name__,
+                                             id(self), self.fp)
+
+    def close(self):
+        self.read = None
+        self.readline = None
+        self.readlines = None
+        self.fileno = None
+        if self.fp: self.fp.close()
+        self.fp = None
+
+class addclosehook(addbase):
+    """Class to add a close hook to an open file."""
+
+    def __init__(self, fp, closehook, *hookargs):
+        addbase.__init__(self, fp)
+        self.closehook = closehook
+        self.hookargs = hookargs
+
+    def close(self):
+        addbase.close(self)
+        if self.closehook:
+            self.closehook(*self.hookargs)
+            self.closehook = None
+            self.hookargs = None
+
+class addinfo(addbase):
+    """class to add an info() method to an open file."""
+
+    def __init__(self, fp, headers):
+        addbase.__init__(self, fp)
+        self.headers = headers
+
+    def info(self):
+        return self.headers
+
+class addinfourl(addbase):
+    """class to add info() and geturl() methods to an open file."""
+
+    def __init__(self, fp, headers, url, code=None):
+        addbase.__init__(self, fp)
+        self.headers = headers
+        self.url = url
+        self.code = code
+
+    def info(self):
+        return self.headers
+
+    def getcode(self):
+        return self.code
+
+    def geturl(self):
+        return self.url
diff --git a/Lib/urllib/robotparser.py b/Lib/urllib/robotparser.py
new file mode 100644
index 0000000000..a91df8d815
--- /dev/null
+++ b/Lib/urllib/robotparser.py
@@ -0,0 +1,191 @@
+""" robotparser.py
+
+    Copyright (C) 2000  Bastian Kleineidam
+
+    You can choose between two licenses when using this package:
+    1) GNU GPLv2
+    2) PSF license for Python 2.2
+
+    The robots.txt Exclusion Protocol is implemented as specified in
+    http://info.webcrawler.com/mak/projects/robots/norobots-rfc.html
+"""
+
+import urllib.parse, urllib.request
+
+__all__ = ["RobotFileParser"]
+
+class RobotFileParser:
+    """ This class provides a set of methods to read, parse and answer
+    questions about a single robots.txt file.
+
+    """
+
+    def __init__(self, url=''):
+        self.entries = []
+        self.default_entry = None
+        self.disallow_all = False
+        self.allow_all = False
+        self.set_url(url)
+        self.last_checked = 0
+
+    def mtime(self):
+        """Returns the time the robots.txt file was last fetched.
+
+        This is useful for long-running web spiders that need to
+        check for new robots.txt files periodically.
+
+        """
+        return self.last_checked
+
+    def modified(self):
+        """Sets the time the robots.txt file was last fetched to the
+        current time.
+
+        """
+        import time
+        self.last_checked = time.time()
+
+    def set_url(self, url):
+        """Sets the URL referring to a robots.txt file."""
+        self.url = url
+        self.host, self.path = urllib.parse.urlparse(url)[1:3]
+
+    def read(self):
+        """Reads the robots.txt URL and feeds it to the parser."""
+        try:
+            f = urllib.request.urlopen(self.url)
+        except urllib.error.HTTPError as err:
+            if err.code in (401, 403):
+                self.disallow_all = True
+            elif err.code >= 400:
+                self.allow_all = True
+        else:
+            self.parse(f.read().splitlines())
+
+    def _add_entry(self, entry):
+        if "*" in entry.useragents:
+            # the default entry is considered last
+            self.default_entry = entry
+        else:
+            self.entries.append(entry)
+
+    def parse(self, lines):
+        """Parse the input lines from a robots.txt file.
+
+        We allow that a user-agent: line is not preceded by
+        one or more blank lines.
+        """
+        state = 0
+        entry = Entry()
+
+        for line in lines:
+            if not line:
+                if state == 1:
+                    entry = Entry()
+                    state = 0
+                elif state == 2:
+                    self._add_entry(entry)
+                    entry = Entry()
+                    state = 0
+            # remove optional comment and strip line
+            i = line.find('#')
+            if i >= 0:
+                line = line[:i]
+            line = line.strip()
+            if not line:
+                continue
+            line = line.split(':', 1)
+            if len(line) == 2:
+                line[0] = line[0].strip().lower()
+                line[1] = urllib.parse.unquote(line[1].strip())
+                if line[0] == "user-agent":
+                    if state == 2:
+                        self._add_entry(entry)
+                        entry = Entry()
+                    entry.useragents.append(line[1])
+                    state = 1
+                elif line[0] == "disallow":
+                    if state != 0:
+                        entry.rulelines.append(RuleLine(line[1], False))
+                        state = 2
+                elif line[0] == "allow":
+                    if state != 0:
+                        entry.rulelines.append(RuleLine(line[1], True))
+        if state == 2:
+            self.entries.append(entry)
+
+
+    def can_fetch(self, useragent, url):
+        """using the parsed robots.txt decide if useragent can fetch url"""
+        if self.disallow_all:
+            return False
+        if self.allow_all:
+            return True
+        # search for given user agent matches
+        # the first match counts
+        url = urllib.parse.quote(urllib.parse.urlparse(urllib.parse.unquote(url))[2]) or "/"
+        for entry in self.entries:
+            if entry.applies_to(useragent):
+                return entry.allowance(url)
+        # try the default entry last
+        if self.default_entry:
+            return self.default_entry.allowance(url)
+        # agent not found ==> access granted
+        return True
+
+    def __str__(self):
+        return ''.join([str(entry) + "\n" for entry in self.entries])
+
+
+class RuleLine:
+    """A rule line is a single "Allow:" (allowance==True) or "Disallow:"
+       (allowance==False) followed by a path."""
+    def __init__(self, path, allowance):
+        if path == '' and not allowance:
+            # an empty value means allow all
+            allowance = True
+        self.path = urllib.parse.quote(path)
+        self.allowance = allowance
+
+    def applies_to(self, filename):
+        return self.path == "*" or filename.startswith(self.path)
+
+    def __str__(self):
+        return (self.allowance and "Allow" or "Disallow") + ": " + self.path
+
+
+class Entry:
+    """An entry has one or more user-agents and zero or more rulelines"""
+    def __init__(self):
+        self.useragents = []
+        self.rulelines = []
+
+    def __str__(self):
+        ret = []
+        for agent in self.useragents:
+            ret.extend(["User-agent: ", agent, "\n"])
+        for line in self.rulelines:
+            ret.extend([str(line), "\n"])
+        return ''.join(ret)
+
+    def applies_to(self, useragent):
+        """check if this entry applies to the specified agent"""
+        # split the name token and make it lower case
+        useragent = useragent.split("/")[0].lower()
+        for agent in self.useragents:
+            if agent == '*':
+                # we have the catch-all agent
+                return True
+            agent = agent.lower()
+            if agent in useragent:
+                return True
+        return False
+
+    def allowance(self, filename):
+        """Preconditions:
+        - our agent applies to this entry
+        - filename is URL decoded"""
+        for line in self.rulelines:
+            if line.applies_to(filename):
+                return line.allowance
+        return True