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+:mod:`packaging.metadata` --- Metadata handling
+===============================================
+
+.. module:: packaging.metadata
+   :synopsis: Class holding the metadata of a release.
+
+
+.. TODO use sphinx-autogen to generate basic doc from the docstrings
+
+.. class:: Metadata
+
+   This class can read and write metadata files complying with any of the
+   defined versions: 1.0 (:PEP:`241`), 1.1 (:PEP:`314`) and 1.2 (:PEP:`345`).  It
+   implements methods to parse Metadata files and write them, and a mapping
+   interface to its contents.
+
+   The :PEP:`345` implementation supports the micro-language for the environment
+   markers, and displays warnings when versions that are supposed to be
+   :PEP:`386`-compliant are violating the specification.
+
+
+Reading metadata
+----------------
+
+The :class:`Metadata` class can be instantiated
+with the path of the metadata file, and provides a dict-like interface to the
+values::
+
+   >>> from packaging.metadata import Metadata
+   >>> metadata = Metadata('PKG-INFO')
+   >>> metadata.keys()[:5]
+   ('Metadata-Version', 'Name', 'Version', 'Platform', 'Supported-Platform')
+   >>> metadata['Name']
+   'CLVault'
+   >>> metadata['Version']
+   '0.5'
+   >>> metadata['Requires-Dist']
+   ["pywin32; sys.platform == 'win32'", "Sphinx"]
+
+
+The fields that support environment markers can be automatically ignored if
+the object is instantiated using the ``platform_dependent`` option.
+:class:`Metadata` will interpret in this case
+the markers and will automatically remove the fields that are not compliant
+with the running environment. Here's an example under Mac OS X. The win32
+dependency we saw earlier is ignored::
+
+   >>> from packaging.metadata import Metadata
+   >>> metadata = Metadata('PKG-INFO', platform_dependent=True)
+   >>> metadata['Requires-Dist']
+   ['Sphinx']
+
+
+If you want to provide your own execution context, let's say to test the
+metadata under a particular environment that is not the current environment,
+you can provide your own values in the ``execution_context`` option, which
+is the dict that may contain one or more keys of the context the micro-language
+expects.
+
+Here's an example, simulating a win32 environment::
+
+   >>> from packaging.metadata import Metadata
+   >>> context = {'sys.platform': 'win32'}
+   >>> metadata = Metadata('PKG-INFO', platform_dependent=True,
+   ...                     execution_context=context)
+   ...
+   >>> metadata['Requires-Dist'] = ["pywin32; sys.platform == 'win32'",
+   ...                              "Sphinx"]
+   ...
+   >>> metadata['Requires-Dist']
+   ['pywin32', 'Sphinx']
+
+
+Writing metadata
+----------------
+
+Writing metadata can be done using the ``write`` method::
+
+   >>> metadata.write('/to/my/PKG-INFO')
+
+The class will pick the best version for the metadata, depending on the values
+provided. If all the values provided exist in all versions, the class will
+use :attr:`PKG_INFO_PREFERRED_VERSION`.  It is set by default to 1.0, the most
+widespread version.
+
+
+Conflict checking and best version
+----------------------------------
+
+Some fields in :PEP:`345` have to comply with the version number specification
+defined in :PEP:`386`.  When they don't comply, a warning is emitted::
+
+   >>> from packaging.metadata import Metadata
+   >>> metadata = Metadata()
+   >>> metadata['Requires-Dist'] = ['Funky (Groovie)']
+   "Funky (Groovie)" is not a valid predicate
+   >>> metadata['Requires-Dist'] = ['Funky (1.2)']
+
+See also :mod:`packaging.version`.
+
+
+.. TODO talk about check()
+
+
+:mod:`packaging.markers` --- Environment markers
+================================================
+
+.. module:: packaging.markers
+   :synopsis: Micro-language for environment markers
+
+
+This is an implementation of environment markers `as defined in PEP 345
+<http://www.python.org/dev/peps/pep-0345/#environment-markers>`_.  It is used
+for some metadata fields.
+
+.. function:: interpret(marker, execution_context=None)
+
+   Interpret a marker and return a boolean result depending on the environment.
+   Example:
+
+      >>> interpret("python_version > '1.0'")
+      True