Remove six

This library no longer supports Python 2, thus usage of six can be
removed.

Change-Id: I8d0c1cfd6dff375b3b7756a5b36c95a2df3f04c6

39 files changed, 180 insertions, 229 deletions

diff --git a/heatclient/common/base.py b/heatclient/common/base.py
index e881511..550a77a 100644
--- a/heatclient/common/base.py
+++ b/heatclient/common/base.py
@@ -24,8 +24,7 @@ import copy
 
 from oslo_utils import reflection
 from oslo_utils import strutils
-import six
-from six.moves.urllib import parse
+from urllib import parse
 
 from heatclient._i18n import _
 from heatclient import exc as exceptions
@@ -207,8 +206,7 @@ class BaseManager(HookableMixin):
         return self.client.delete(url)
 
 
-@six.add_metaclass(abc.ABCMeta)
-class ManagerWithFind(BaseManager):
+class ManagerWithFind(BaseManager, metaclass=abc.ABCMeta):
     """Manager with additional `find()`/`findall()` methods."""
 
     @abc.abstractmethod
diff --git a/heatclient/common/deployment_utils.py b/heatclient/common/deployment_utils.py
index c44da2f..90ce66d 100644
--- a/heatclient/common/deployment_utils.py
+++ b/heatclient/common/deployment_utils.py
@@ -13,10 +13,9 @@
 import copy
 import uuid
 
-import six
-from six.moves.urllib import parse as urlparse
 from swiftclient import client as sc
 from swiftclient import utils as swiftclient_utils
+from urllib import parse as urlparse
 
 from heatclient._i18n import _
 from heatclient import exc
@@ -102,7 +101,7 @@ def create_temp_url(swift_client, name, timeout, container=None):
     key_header = 'x-account-meta-temp-url-key'
     if key_header not in swift_client.head_account():
         swift_client.post_account({
-            key_header: six.text_type(uuid.uuid4())[:32]})
+            key_header: str(uuid.uuid4())[:32]})
 
     key = swift_client.head_account()[key_header]
     project_path = swift_client.url.split('/')[-1]
diff --git a/heatclient/common/format_utils.py b/heatclient/common/format_utils.py
index d1a9206..598ae9e 100644
--- a/heatclient/common/format_utils.py
+++ b/heatclient/common/format_utils.py
@@ -15,7 +15,6 @@
 import sys
 
 from osc_lib.command import command
-import six
 
 
 class RawFormat(command.ShowOne):
@@ -63,7 +62,7 @@ def indent_and_truncate(txt, spaces=0, truncate=False, truncate_limit=10,
     """
     if txt is None:
         return
-    lines = six.text_type(txt).splitlines()
+    lines = str(txt).splitlines()
     if truncate and len(lines) > truncate_limit:
         lines = lines[-truncate_limit:]
         if truncate_prefix is not None:
diff --git a/heatclient/common/http.py b/heatclient/common/http.py
index 3a85bc5..f71ca66 100644
--- a/heatclient/common/http.py
+++ b/heatclient/common/http.py
@@ -24,8 +24,7 @@ from oslo_serialization import jsonutils
 from oslo_utils import encodeutils
 from oslo_utils import importutils
 import requests
-import six
-from six.moves.urllib import parse
+from urllib import parse
 
 from heatclient._i18n import _
 from heatclient.common import utils
@@ -151,7 +150,7 @@ class HTTPClient(object):
         dump.append('')
         if resp.content:
             content = resp.content
-            if isinstance(content, six.binary_type):
+            if isinstance(content, bytes):
                 content = content.decode()
             dump.extend([content, ''])
         LOG.debug('\n'.join(dump))
diff --git a/heatclient/common/template_utils.py b/heatclient/common/template_utils.py
index ebabc04..cc81435 100644
--- a/heatclient/common/template_utils.py
+++ b/heatclient/common/template_utils.py
@@ -15,10 +15,9 @@
 
 from collections import abc
 from oslo_serialization import jsonutils
-import six
-from six.moves.urllib import error
-from six.moves.urllib import parse
-from six.moves.urllib import request
+from urllib import error
+from urllib import parse
+from urllib import request
 
 from heatclient._i18n import _
 from heatclient.common import environment_format
@@ -92,7 +91,7 @@ def get_template_contents(template_file=None, template_url=None,
                                % template_url)
 
     try:
-        if isinstance(tpl, six.binary_type):
+        if isinstance(tpl, bytes):
             tpl = tpl.decode('utf-8')
         template = template_format.parse(tpl)
     except ValueError as e:
@@ -114,7 +113,7 @@ def resolve_template_get_files(template, files, template_base_url,
     def ignore_if(key, value):
         if key != 'get_file' and key != 'type':
             return True
-        if not isinstance(value, six.string_types):
+        if not isinstance(value, str):
             return True
         if (key == 'type' and
                 not value.endswith(('.yaml', '.template'))):
@@ -130,7 +129,7 @@ def resolve_template_get_files(template, files, template_base_url,
 
 def is_template(file_content):
     try:
-        if isinstance(file_content, six.binary_type):
+        if isinstance(file_content, bytes):
             file_content = file_content.decode('utf-8')
         template_format.parse(file_content)
     except (ValueError, TypeError):
@@ -144,7 +143,7 @@ def get_file_contents(from_data, files, base_url=None,
 
     if recurse_if and recurse_if(from_data):
         if isinstance(from_data, dict):
-            recurse_data = six.itervalues(from_data)
+            recurse_data = from_data.values()
         else:
             recurse_data = from_data
         for value in recurse_data:
diff --git a/heatclient/common/utils.py b/heatclient/common/utils.py
index 3d82f98..869c297 100644
--- a/heatclient/common/utils.py
+++ b/heatclient/common/utils.py
@@ -22,10 +22,9 @@ import uuid
 from oslo_serialization import jsonutils
 from oslo_utils import encodeutils
 import prettytable
-import six
-from six.moves.urllib import error
-from six.moves.urllib import parse
-from six.moves.urllib import request
+from urllib import error
+from urllib import parse
+from urllib import request
 import yaml
 
 from heatclient._i18n import _
@@ -123,10 +122,7 @@ def print_list(objs, fields, formatters=None, sortby_index=0,
                 row.append(data)
         pt.add_row(row)
 
-    if six.PY3:
-        print(encodeutils.safe_encode(pt.get_string(**kwargs)).decode())
-    else:
-        print(encodeutils.safe_encode(pt.get_string(**kwargs)))
+    print(encodeutils.safe_encode(pt.get_string(**kwargs)).decode())
 
 
 def link_formatter(links):
@@ -286,10 +282,7 @@ def print_update_list(lst, fields, formatters=None):
 
         pt.add_row(row)
 
-    if six.PY3:
-        print(encodeutils.safe_encode(pt.get_string()).decode())
-    else:
-        print(encodeutils.safe_encode(pt.get_string()))
+    print(encodeutils.safe_encode(pt.get_string()).decode())
 
 
 def find_resource(manager, name_or_id):
diff --git a/heatclient/osc/v1/build_info.py b/heatclient/osc/v1/build_info.py
index 9f90dd5..cd4700a 100644
--- a/heatclient/osc/v1/build_info.py
+++ b/heatclient/osc/v1/build_info.py
@@ -17,7 +17,6 @@ import logging
 
 from osc_lib.command import command
 from osc_lib import utils
-import six
 
 from heatclient.common import utils as heat_utils
 
@@ -41,6 +40,6 @@ class BuildInfo(command.ShowOne):
             'api': heat_utils.json_formatter,
             'engine': heat_utils.json_formatter,
         }
-        columns = sorted(list(six.iterkeys(result)))
+        columns = sorted(list(result.keys()))
         return columns, utils.get_dict_properties(result, columns,
                                                   formatters=formatters)
diff --git a/heatclient/osc/v1/resource.py b/heatclient/osc/v1/resource.py
index e29b077..a30bae2 100644
--- a/heatclient/osc/v1/resource.py
+++ b/heatclient/osc/v1/resource.py
@@ -20,8 +20,7 @@ from osc_lib import exceptions as exc
 from osc_lib.i18n import _
 from osc_lib import utils
 from oslo_serialization import jsonutils
-import six
-from six.moves.urllib import request
+from urllib import request
 
 from heatclient.common import format_utils
 from heatclient.common import utils as heat_utils
@@ -184,8 +183,8 @@ def _resource_metadata(heat_client, args):
                                {'stack': args.stack,
                                 'resource': args.resource})
 
-    data = list(six.itervalues(metadata))
-    columns = list(six.iterkeys(metadata))
+    data = list(metadata.values())
+    columns = list(metadata.keys())
     return columns, data
 
 
diff --git a/heatclient/osc/v1/resource_type.py b/heatclient/osc/v1/resource_type.py
index 6d55ab5..128b6dc 100644
--- a/heatclient/osc/v1/resource_type.py
+++ b/heatclient/osc/v1/resource_type.py
@@ -18,7 +18,6 @@ import logging
 from osc_lib.command import command
 from osc_lib import exceptions as exc
 from osc_lib.i18n import _
-import six
 
 from heatclient.common import format_utils
 from heatclient.common import utils as heat_utils
@@ -80,8 +79,8 @@ def _show_resourcetype(heat_client, parsed_args):
         raise exc.CommandError(
             _('Resource type not found: %s') % parsed_args.resource_type)
 
-    rows = list(six.itervalues(data))
-    columns = list(six.iterkeys(data))
+    rows = list(data.values())
+    columns = list(data.keys())
     return columns, rows
 
 
diff --git a/heatclient/osc/v1/snapshot.py b/heatclient/osc/v1/snapshot.py
index b07add9..8088285 100644
--- a/heatclient/osc/v1/snapshot.py
+++ b/heatclient/osc/v1/snapshot.py
@@ -20,7 +20,6 @@ from osc_lib.command import command
 from osc_lib import exceptions as exc
 from osc_lib.i18n import _
 from osc_lib import utils
-import six
 
 from heatclient.common import format_utils
 from heatclient import exc as heat_exc
@@ -95,8 +94,8 @@ class ShowSnapshot(format_utils.YamlFormat):
                                    % {'snapshot_id': snapshot_id,
                                       'stack_id': stack_id})
 
-        rows = list(six.itervalues(data))
-        columns = list(six.iterkeys(data))
+        rows = list(data.values())
+        columns = list(data.keys())
         return columns, rows
 
 
diff --git a/heatclient/osc/v1/software_config.py b/heatclient/osc/v1/software_config.py
index af27be7..41eccd2 100644
--- a/heatclient/osc/v1/software_config.py
+++ b/heatclient/osc/v1/software_config.py
@@ -18,8 +18,7 @@ import logging
 from osc_lib.command import command
 from osc_lib import exceptions as exc
 from osc_lib import utils
-import six
-from six.moves.urllib import request
+from urllib import request
 import yaml
 
 from heatclient._i18n import _
@@ -181,8 +180,8 @@ def _create_config(heat_client, args):
 
     config['name'] = args.name
     sc = heat_client.software_configs.create(**config).to_dict()
-    rows = list(six.itervalues(sc))
-    columns = list(six.iterkeys(sc))
+    rows = list(sc.values())
+    columns = list(sc.keys())
     return columns, rows
 
 
diff --git a/heatclient/osc/v1/stack.py b/heatclient/osc/v1/stack.py
index a25844b..583e18b 100644
--- a/heatclient/osc/v1/stack.py
+++ b/heatclient/osc/v1/stack.py
@@ -20,8 +20,7 @@ from osc_lib.command import command
 from osc_lib import exceptions as exc
 from osc_lib import utils
 from oslo_serialization import jsonutils
-import six
-from six.moves.urllib import request
+from urllib import request
 import yaml
 
 from heatclient._i18n import _
@@ -733,7 +732,7 @@ class DeleteStack(command.Command):
 
         try:
             if not parsed_args.yes and sys.stdin.isatty():
-                prompt_response = six.moves.input(
+                prompt_response = input(
                     _("Are you sure you want to delete this stack(s) [y/N]? ")
                 ).lower()
                 if not prompt_response.startswith('y'):
@@ -919,8 +918,8 @@ class AbandonStack(format_utils.JsonFormat):
             except IOError as e:
                 raise exc.CommandError(str(e))
 
-        data = list(six.itervalues(stack))
-        columns = list(six.iterkeys(stack))
+        data = list(stack.values())
+        columns = list(stack.keys())
         return columns, data
 
 
@@ -963,8 +962,8 @@ class ExportStack(format_utils.JsonFormat):
             except IOError as e:
                 raise exc.CommandError(str(e))
 
-        data = list(six.itervalues(data_info))
-        columns = list(six.iterkeys(data_info))
+        data = list(data_info.values())
+        columns = list(data_info.keys())
         return columns, data
 
 
diff --git a/heatclient/osc/v1/template.py b/heatclient/osc/v1/template.py
index f25263e..ef29790 100644
--- a/heatclient/osc/v1/template.py
+++ b/heatclient/osc/v1/template.py
@@ -16,7 +16,6 @@ import logging
 
 from osc_lib.command import command
 from osc_lib import utils
-import six
 
 from heatclient._i18n import _
 from heatclient.common import format_utils
@@ -181,6 +180,6 @@ def _validate(heat_client, args):
         fields['files_container'] = args.files_container
 
     validation = heat_client.stacks.validate(**fields)
-    data = list(six.itervalues(validation))
-    columns = list(six.iterkeys(validation))
+    data = list(validation.values())
+    columns = list(validation.keys())
     return columns, data
diff --git a/heatclient/shell.py b/heatclient/shell.py
index cf143bf..9123bac 100644
--- a/heatclient/shell.py
+++ b/heatclient/shell.py
@@ -22,7 +22,6 @@ from keystoneauth1.identity import generic
 from keystoneauth1 import session as kssession
 from oslo_utils import encodeutils
 from oslo_utils import importutils
-import six
 
 import heatclient
 from heatclient._i18n import _
@@ -610,7 +609,7 @@ def main(args=None):
         if '--debug' in args or '-d' in args:
             raise
         else:
-            print(encodeutils.safe_encode(six.text_type(e)), file=sys.stderr)
+            print(encodeutils.safe_encode(str(e)), file=sys.stderr)
         sys.exit(1)
 
 
diff --git a/heatclient/tests/functional/osc/v1/base.py b/heatclient/tests/functional/osc/v1/base.py
index 591225a..1befa0e 100644
--- a/heatclient/tests/functional/osc/v1/base.py
+++ b/heatclient/tests/functional/osc/v1/base.py
@@ -12,7 +12,6 @@
 
 import os
 
-import six
 from tempest.lib.cli import base
 from tempest.lib.cli import output_parser
 from tempest.lib import exceptions as tempest_exc
@@ -48,7 +47,7 @@ class OpenStackClientTestBase(base.ClientTestBase):
         obj = {}
         items = self.parser.listing(output)
         for item in items:
-            obj[item['Field']] = six.text_type(item['Value'])
+            obj[item['Field']] = str(item['Value'])
         return dict((self._key_name(k), v) for k, v in obj.items())
 
     def _key_name(self, key):
@@ -86,7 +85,7 @@ class OpenStackClientTestBase(base.ClientTestBase):
                 self.openstack(cmd)
             except tempest_exc.CommandFailed as e:
                 msg = "Stack not found: %s" % id
-                if msg in six.text_type(e.stdout):
+                if msg in str(e.stdout):
                     return
                 raise
 
diff --git a/heatclient/tests/unit/osc/fakes.py b/heatclient/tests/unit/osc/fakes.py
index ba624ad..e45cab1 100644
--- a/heatclient/tests/unit/osc/fakes.py
+++ b/heatclient/tests/unit/osc/fakes.py
@@ -16,7 +16,6 @@
 import json
 
 import requests
-import six
 
 
 class FakeStdout(object):
@@ -41,5 +40,5 @@ class FakeResponse(requests.Response):
 
         self.headers.update(headers)
         self._content = json.dumps(data)
-        if not isinstance(self._content, six.binary_type):
+        if not isinstance(self._content, bytes):
             self._content = self._content.encode()
diff --git a/heatclient/tests/unit/osc/v1/test_resource.py b/heatclient/tests/unit/osc/v1/test_resource.py
index b932f7e..8d0b314 100644
--- a/heatclient/tests/unit/osc/v1/test_resource.py
+++ b/heatclient/tests/unit/osc/v1/test_resource.py
@@ -305,7 +305,7 @@ class TestResourceSignal(TestResource):
         self.assertEqual('Should only specify one of data or data-file',
                          str(error))
 
-    @mock.patch('six.moves.urllib.request.urlopen')
+    @mock.patch('urllib.request.urlopen')
     def test_resource_signal_file(self, urlopen):
         data = mock.Mock()
         data.read.side_effect = ['{"message":"Content"}']
diff --git a/heatclient/tests/unit/osc/v1/test_snapshot.py b/heatclient/tests/unit/osc/v1/test_snapshot.py
index 1b99942..6b58303 100644
--- a/heatclient/tests/unit/osc/v1/test_snapshot.py
+++ b/heatclient/tests/unit/osc/v1/test_snapshot.py
@@ -12,8 +12,8 @@
 
 from unittest import mock
 
+import io
 from osc_lib import exceptions as exc
-import six
 
 from heatclient import exc as heat_exc
 from heatclient.osc.v1 import snapshot
@@ -160,7 +160,7 @@ class TestSnapshotDelete(TestStack):
             self.cmd.take_action,
             parsed_args)
 
-    @mock.patch('sys.stdin', spec=six.StringIO)
+    @mock.patch('sys.stdin', spec=io.StringIO)
     def test_snapshot_delete_prompt(self, mock_stdin):
         arglist = ['my_stack', 'snapshot_id']
         mock_stdin.isatty.return_value = True
@@ -173,7 +173,7 @@ class TestSnapshotDelete(TestStack):
         self.stack_client.snapshot_delete.assert_called_with('my_stack',
                                                              'snapshot_id')
 
-    @mock.patch('sys.stdin', spec=six.StringIO)
+    @mock.patch('sys.stdin', spec=io.StringIO)
     def test_snapshot_delete_prompt_no(self, mock_stdin):
         arglist = ['my_stack', 'snapshot_id']
         mock_stdin.isatty.return_value = True
diff --git a/heatclient/tests/unit/osc/v1/test_software_config.py b/heatclient/tests/unit/osc/v1/test_software_config.py
index 470de12..f2afcb1 100644
--- a/heatclient/tests/unit/osc/v1/test_software_config.py
+++ b/heatclient/tests/unit/osc/v1/test_software_config.py
@@ -145,7 +145,7 @@ class TestCreateConfig(TestConfig):
         self.mock_client.software_configs.create.assert_called_with(
             **properties)
 
-    @mock.patch('six.moves.urllib.request.urlopen')
+    @mock.patch('urllib.request.urlopen')
     def test_config_create_config_file(self, urlopen):
         properties = {
             'config': 'config',
@@ -172,7 +172,7 @@ class TestCreateConfig(TestConfig):
         self.mock_client.software_configs.create.assert_called_with(
             **properties)
 
-    @mock.patch('six.moves.urllib.request.urlopen')
+    @mock.patch('urllib.request.urlopen')
     def test_config_create_definition_file(self, urlopen):
         definition = {
             'inputs': [
diff --git a/heatclient/tests/unit/osc/v1/test_stack.py b/heatclient/tests/unit/osc/v1/test_stack.py
index 7af48ff..49dc8e9 100644
--- a/heatclient/tests/unit/osc/v1/test_stack.py
+++ b/heatclient/tests/unit/osc/v1/test_stack.py
@@ -17,7 +17,6 @@ from unittest import mock
 
 from osc_lib import exceptions as exc
 from osc_lib import utils
-import six
 import testscenarios
 import yaml
 
@@ -274,7 +273,7 @@ class TestStackUpdate(TestStack):
 
         ex = self.assertRaises(exc.CommandError, self.cmd.take_action,
                                parsed_args)
-        self.assertEqual("--rollback invalid value: foo", six.text_type(ex))
+        self.assertEqual("--rollback invalid value: foo", str(ex))
 
     def test_stack_update_parameters(self):
         template_path = ('/'.join(self.template_path.split('/')[:-1]) +
@@ -720,7 +719,7 @@ class TestStackDelete(TestStack):
         self.stack_client.delete.assert_any_call('stack3')
         self.assertEqual('Unable to delete 1 of the 3 stacks.', str(error))
 
-    @mock.patch('sys.stdin', spec=six.StringIO)
+    @mock.patch('sys.stdin', spec=io.StringIO)
     def test_stack_delete_prompt(self, mock_stdin):
         arglist = ['my_stack']
         mock_stdin.isatty.return_value = True
@@ -732,7 +731,7 @@ class TestStackDelete(TestStack):
         mock_stdin.readline.assert_called_with()
         self.stack_client.delete.assert_called_with('my_stack')
 
-    @mock.patch('sys.stdin', spec=six.StringIO)
+    @mock.patch('sys.stdin', spec=io.StringIO)
     def test_stack_delete_prompt_no(self, mock_stdin):
         arglist = ['my_stack']
         mock_stdin.isatty.return_value = True
diff --git a/heatclient/tests/unit/test_common_http.py b/heatclient/tests/unit/test_common_http.py
index 1d32ba1..eb124ca 100644
--- a/heatclient/tests/unit/test_common_http.py
+++ b/heatclient/tests/unit/test_common_http.py
@@ -15,9 +15,9 @@
 import socket
 from unittest import mock
 
+import io
 from keystoneauth1 import adapter
 from oslo_serialization import jsonutils
-import six
 import testtools
 
 from heatclient.common import http
@@ -608,7 +608,7 @@ class SessionClientTest(testtools.TestCase):
         e = self.assertRaises(exc.HTTPNotFound,
                               client.request, '', 'GET')
         # Assert that the raised exception can be converted to string
-        self.assertIsNotNone(six.text_type(e))
+        self.assertIsNotNone(str(e))
 
     def test_redirect_302_location(self):
         fake1 = fakes.FakeHTTPResponse(
@@ -687,7 +687,7 @@ class SessionClientTest(testtools.TestCase):
                                     auth=mock.ANY)
         e = self.assertRaises(exc.InvalidEndpoint,
                               client.request, '', 'GET', redirect=True)
-        self.assertEqual("Location not returned with 302", six.text_type(e))
+        self.assertEqual("Location not returned with 302", str(e))
 
     def test_no_redirect_302_no_location(self):
         fake = fakes.FakeHTTPResponse(
@@ -716,7 +716,7 @@ class SessionClientTest(testtools.TestCase):
         e = self.assertRaises(exc.HTTPMultipleChoices,
                               client.request, '', 'GET')
         # Assert that the raised exception can be converted to string
-        self.assertIsNotNone(six.text_type(e))
+        self.assertIsNotNone(str(e))
 
     def test_504_error_response(self):
         # for 504 we don't have specific exception type
@@ -766,7 +766,7 @@ class SessionClientTest(testtools.TestCase):
             {}
         )
         mock_dumps.return_value = "{'files': test}}"
-        data = six.BytesIO(b'test')
+        data = io.BytesIO(b'test')
         kwargs = {'endpoint_override': 'http://no.where/',
                   'data': {'files': data}}
         client = http.SessionClient(mock.ANY)
diff --git a/heatclient/tests/unit/test_deployment_utils.py b/heatclient/tests/unit/test_deployment_utils.py
index 4a5dc13..d9a7857 100644
--- a/heatclient/tests/unit/test_deployment_utils.py
+++ b/heatclient/tests/unit/test_deployment_utils.py
@@ -13,7 +13,6 @@
 
 from unittest import mock
 
-import six
 import swiftclient.client
 import testscenarios
 import testtools
@@ -231,7 +230,7 @@ class DerivedConfigTest(testtools.TestCase):
             if not self.result_error:
                 raise e
             self.assertIsInstance(e, self.result_error)
-            self.assertEqual(self.result_error_msg, six.text_type(e))
+            self.assertEqual(self.result_error_msg, str(e))
 
 
 class TempURLSignalTest(testtools.TestCase):
@@ -331,7 +330,7 @@ class TempURLSignalTest(testtools.TestCase):
         self.assertEqual((
             'Cannot use --os-no-client-auth, auth required to create '
             'a Swift TempURL.'),
-            six.text_type(e))
+            str(e))
 
     @mock.patch.object(deployment_utils, 'create_temp_url')
     @mock.patch.object(deployment_utils, 'create_swift_client')
diff --git a/heatclient/tests/unit/test_environment_format.py b/heatclient/tests/unit/test_environment_format.py
index e2a86a8..86ab0c2 100644
--- a/heatclient/tests/unit/test_environment_format.py
+++ b/heatclient/tests/unit/test_environment_format.py
@@ -12,7 +12,6 @@
 
 from unittest import mock
 
-import six
 import testscenarios
 import testtools
 import yaml
@@ -106,4 +105,4 @@ but very:
   - incorrect
 """
         ex = self.assertRaises(ValueError, environment_format.parse, yaml)
-        self.assertIn('but very:\n            ^', six.text_type(ex))
+        self.assertIn('but very:\n            ^', str(ex))
diff --git a/heatclient/tests/unit/test_format_utils.py b/heatclient/tests/unit/test_format_utils.py
index 28806d4..4f149fb 100644
--- a/heatclient/tests/unit/test_format_utils.py
+++ b/heatclient/tests/unit/test_format_utils.py
@@ -12,8 +12,8 @@
 #
 #   Copyright 2015 IBM Corp.
 
+import io
 import json
-import six
 import yaml
 
 from heatclient.common import format_utils
@@ -128,7 +128,7 @@ abcde
                 truncate_postfix='truncated'))
 
     def test_print_software_deployment_output(self):
-        out = six.StringIO()
+        out = io.StringIO()
         format_utils.print_software_deployment_output(
             {'deploy_stdout': ''}, out=out, name='deploy_stdout')
         self.assertEqual(
@@ -137,7 +137,7 @@ abcde
         ov = {'deploy_stdout': '', 'deploy_stderr': '1\n2\n3\n4\n5\n6\n7\n8\n9'
                                                     '\n10\n11',
               'deploy_status_code': 0}
-        out = six.StringIO()
+        out = io.StringIO()
         format_utils.print_software_deployment_output(ov, out=out,
                                                       name='deploy_stderr')
         self.assertEqual(
@@ -156,7 +156,7 @@ abcde
     11
     (truncated, view all with --long)
 ''', out.getvalue())
-        out = six.StringIO()
+        out = io.StringIO()
         format_utils.print_software_deployment_output(ov, out=out,
                                                       name='deploy_stderr',
                                                       long=True)
diff --git a/heatclient/tests/unit/test_resource_formatter.py b/heatclient/tests/unit/test_resource_formatter.py
index 073e12f..f69f649 100644
--- a/heatclient/tests/unit/test_resource_formatter.py
+++ b/heatclient/tests/unit/test_resource_formatter.py
@@ -14,7 +14,7 @@
 import json
 import os
 
-import six
+import io
 
 from heatclient.common import resource_formatter
 from heatclient.osc.v1 import resource
@@ -94,7 +94,7 @@ OS::Heat::RandomString" ];
             self.resources.append(v1_resources.Resource(None, r))
 
     def test_resource_list(self):
-        out = six.StringIO()
+        out = io.StringIO()
         formatter = resource_formatter.ResourceDotFormatter()
         formatter.emit_list(None, self.resources, out, None)
 
diff --git a/heatclient/tests/unit/test_resources.py b/heatclient/tests/unit/test_resources.py
index 65285e9..8728238 100644
--- a/heatclient/tests/unit/test_resources.py
+++ b/heatclient/tests/unit/test_resources.py
@@ -14,8 +14,8 @@
 
 from unittest import mock
 
-from six.moves.urllib import parse
 import testtools
+from urllib import parse
 
 from heatclient.common import utils
 from heatclient.v1 import resources
diff --git a/heatclient/tests/unit/test_shell.py b/heatclient/tests/unit/test_shell.py
index c29a3a2..495588b 100644
--- a/heatclient/tests/unit/test_shell.py
+++ b/heatclient/tests/unit/test_shell.py
@@ -18,15 +18,15 @@ from unittest import mock
 import uuid
 
 import fixtures
+import io
 from keystoneauth1 import fixture as keystone_fixture
 from oslo_serialization import jsonutils
 from oslo_utils import encodeutils
 from requests_mock.contrib import fixture as rm_fixture
-import six
-from six.moves.urllib import parse
-from six.moves.urllib import request
 import testscenarios
 import testtools
+from urllib import parse
+from urllib import request
 import yaml
 
 from heatclient._i18n import _
@@ -411,7 +411,7 @@ class ShellBase(TestCase):
     def shell(self, argstr):
         orig = sys.stdout
         try:
-            sys.stdout = six.StringIO()
+            sys.stdout = io.StringIO()
             _shell = heatclient.shell.HeatShell()
             _shell.main(argstr.split())
             self.subcommands = _shell.subcommands.keys()
@@ -525,7 +525,7 @@ class ShellTestNoMoxBase(TestCase):
     def shell(self, argstr):
         orig = sys.stdout
         try:
-            sys.stdout = six.StringIO()
+            sys.stdout = io.StringIO()
             _shell = heatclient.shell.HeatShell()
             _shell.main(argstr.split())
             self.subcommands = _shell.subcommands.keys()
@@ -1354,7 +1354,7 @@ class ShellTestUserPass(ShellBase):
 
     def test_stack_create_url(self):
         self.register_keystone_auth_fixture()
-        url_content = six.StringIO(
+        url_content = io.StringIO(
             '{"AWSTemplateFormatVersion" : "2010-09-09"}')
         self.useFixture(fixtures.MockPatchObject(request, 'urlopen',
                                                  return_value=url_content))
@@ -2001,7 +2001,7 @@ class ShellTestUserPass(ShellBase):
 
     # the main thing this @mock.patch is doing here is keeping
     # sys.stdin untouched for later tests
-    @mock.patch('sys.stdin', new_callable=six.StringIO)
+    @mock.patch('sys.stdin', new_callable=io.StringIO)
     def test_stack_delete_prompt_with_tty(self, ms):
         self.register_keystone_auth_fixture()
         mock_stdin = mock.Mock()
@@ -2025,7 +2025,7 @@ class ShellTestUserPass(ShellBase):
 
     # the main thing this @mock.patch is doing here is keeping
     # sys.stdin untouched for later tests
-    @mock.patch('sys.stdin', new_callable=six.StringIO)
+    @mock.patch('sys.stdin', new_callable=io.StringIO)
     def test_stack_delete_prompt_with_tty_y(self, ms):
         self.register_keystone_auth_fixture()
         mock_stdin = mock.Mock()
@@ -2159,7 +2159,7 @@ class ShellTestUserPass(ShellBase):
 
     # the main thing this @mock.patch is doing here is keeping
     # sys.stdin untouched for later tests
-    @mock.patch('sys.stdin', new_callable=six.StringIO)
+    @mock.patch('sys.stdin', new_callable=io.StringIO)
     def test_snapshot_delete_prompt_with_tty(self, ms):
         self.register_keystone_auth_fixture()
         resp_dict = {"snapshot": {
@@ -2189,7 +2189,7 @@ class ShellTestUserPass(ShellBase):
 
     # the main thing this @mock.patch is doing here is keeping
     # sys.stdin untouched for later tests
-    @mock.patch('sys.stdin', new_callable=six.StringIO)
+    @mock.patch('sys.stdin', new_callable=io.StringIO)
     def test_snapshot_delete_prompt_with_tty_y(self, ms):
         self.register_keystone_auth_fixture()
         resp_dict = {"snapshot": {
@@ -2477,7 +2477,7 @@ class ShellTestUserPass(ShellBase):
             exc.CommandError, self.shell,
             'output-show teststack/1 output1')
         self.assertIn('The Referenced Attribute (0 PublicIP) is incorrect.',
-                      six.text_type(error))
+                      str(error))
 
 
 class ShellTestActions(ShellBase):
@@ -3548,8 +3548,8 @@ class ShellTestConfig(ShellBase):
         }}
 
         output = [
-            six.StringIO(yaml.safe_dump(definition, indent=2)),
-            six.StringIO('the config script'),
+            io.StringIO(yaml.safe_dump(definition, indent=2)),
+            io.StringIO('the config script'),
         ]
         self.useFixture(fixtures.MockPatchObject(request, 'urlopen',
                                                  side_effect=output))
@@ -4082,7 +4082,7 @@ class MockShellBase(TestCase):
     def shell(self, argstr):
         orig = sys.stdout
         try:
-            sys.stdout = six.StringIO()
+            sys.stdout = io.StringIO()
             _shell = heatclient.shell.HeatShell()
             _shell.main(argstr.split())
             self.subcommands = _shell.subcommands.keys()
diff --git a/heatclient/tests/unit/test_template_format.py b/heatclient/tests/unit/test_template_format.py
index ab2aa1a..479bbac 100644
--- a/heatclient/tests/unit/test_template_format.py
+++ b/heatclient/tests/unit/test_template_format.py
@@ -12,7 +12,6 @@
 
 from unittest import mock
 
-import six
 import testscenarios
 import testtools
 import yaml
@@ -60,4 +59,4 @@ but very:
   - incorrect
 """
         ex = self.assertRaises(ValueError, template_format.parse, yaml)
-        self.assertIn('but very:\n            ^', six.text_type(ex))
+        self.assertIn('but very:\n            ^', str(ex))
diff --git a/heatclient/tests/unit/test_template_utils.py b/heatclient/tests/unit/test_template_utils.py
index a13d7ae..1820278 100644
--- a/heatclient/tests/unit/test_template_utils.py
+++ b/heatclient/tests/unit/test_template_utils.py
@@ -15,11 +15,11 @@ import json
 import tempfile
 from unittest import mock
 
+import io
 from oslo_serialization import base64
-import six
-from six.moves.urllib import error
 import testtools
 from testtools import matchers
+from urllib import error
 import yaml
 
 from heatclient.common import template_utils
@@ -37,8 +37,8 @@ class ShellEnvironmentTest(testtools.TestCase):
         if url:
             def side_effect(args):
                 if url == args:
-                    return six.BytesIO(content)
-            with mock.patch('six.moves.urllib.request.urlopen') as mock_url:
+                    return io.BytesIO(content)
+            with mock.patch('urllib.request.urlopen') as mock_url:
                 mock_url.side_effect = side_effect
                 template_utils.resolve_environment_urls(
                     jenv.get('resource_registry'), files, env_base_url)
@@ -47,7 +47,7 @@ class ShellEnvironmentTest(testtools.TestCase):
             template_utils.resolve_environment_urls(
                 jenv.get('resource_registry'), files, env_base_url)
 
-    @mock.patch('six.moves.urllib.request.urlopen')
+    @mock.patch('urllib.request.urlopen')
     def test_ignore_env_keys(self, mock_url):
         env_file = '/home/my/dir/env.yaml'
         env = b'''
@@ -57,7 +57,7 @@ class ShellEnvironmentTest(testtools.TestCase):
               hooks: pre_create
               restricted_actions: replace
         '''
-        mock_url.return_value = six.BytesIO(env)
+        mock_url.return_value = io.BytesIO(env)
         _, env_dict = template_utils.process_environment_and_files(
             env_file)
         self.assertEqual(
@@ -67,7 +67,7 @@ class ShellEnvironmentTest(testtools.TestCase):
             env_dict)
         mock_url.assert_called_with('file://%s' % env_file)
 
-    @mock.patch('six.moves.urllib.request.urlopen')
+    @mock.patch('urllib.request.urlopen')
     def test_process_environment_file(self, mock_url):
 
         env_file = '/home/my/dir/env.yaml'
@@ -75,8 +75,8 @@ class ShellEnvironmentTest(testtools.TestCase):
         resource_registry:
           "OS::Thingy": "file:///home/b/a.yaml"
         '''
-        mock_url.side_effect = [six.BytesIO(env), six.BytesIO(self.template_a),
-                                six.BytesIO(self.template_a)]
+        mock_url.side_effect = [io.BytesIO(env), io.BytesIO(self.template_a),
+                                io.BytesIO(self.template_a)]
 
         files, env_dict = template_utils.process_environment_and_files(
             env_file)
@@ -92,7 +92,7 @@ class ShellEnvironmentTest(testtools.TestCase):
             mock.call('file:///home/b/a.yaml')
         ])
 
-    @mock.patch('six.moves.urllib.request.urlopen')
+    @mock.patch('urllib.request.urlopen')
     def test_process_environment_relative_file(self, mock_url):
 
         env_file = '/home/my/dir/env.yaml'
@@ -102,8 +102,8 @@ class ShellEnvironmentTest(testtools.TestCase):
           "OS::Thingy": a.yaml
         '''
 
-        mock_url.side_effect = [six.BytesIO(env), six.BytesIO(self.template_a),
-                                six.BytesIO(self.template_a)]
+        mock_url.side_effect = [io.BytesIO(env), io.BytesIO(self.template_a),
+                                io.BytesIO(self.template_a)]
 
         self.assertEqual(
             env_url,
@@ -139,7 +139,7 @@ class ShellEnvironmentTest(testtools.TestCase):
         self.assertEqual({}, files)
         self.assertEqual({}, env)
 
-    @mock.patch('six.moves.urllib.request.urlopen')
+    @mock.patch('urllib.request.urlopen')
     def test_process_environment_relative_file_up(self, mock_url):
 
         env_file = '/home/my/dir/env.yaml'
@@ -148,8 +148,8 @@ class ShellEnvironmentTest(testtools.TestCase):
         resource_registry:
           "OS::Thingy": ../bar/a.yaml
         '''
-        mock_url.side_effect = [six.BytesIO(env), six.BytesIO(self.template_a),
-                                six.BytesIO(self.template_a)]
+        mock_url.side_effect = [io.BytesIO(env), io.BytesIO(self.template_a),
+                                io.BytesIO(self.template_a)]
 
         env_url = 'file://%s' % env_file
         self.assertEqual(
@@ -174,7 +174,7 @@ class ShellEnvironmentTest(testtools.TestCase):
             mock.call('file:///home/my/bar/a.yaml')
         ])
 
-    @mock.patch('six.moves.urllib.request.urlopen')
+    @mock.patch('urllib.request.urlopen')
     def test_process_environment_url(self, mock_url):
         env = b'''
         resource_registry:
@@ -182,8 +182,8 @@ class ShellEnvironmentTest(testtools.TestCase):
         '''
         url = 'http://no.where/some/path/to/file.yaml'
         tmpl_url = 'http://no.where/some/path/to/a.yaml'
-        mock_url.side_effect = [six.BytesIO(env), six.BytesIO(self.template_a),
-                                six.BytesIO(self.template_a)]
+        mock_url.side_effect = [io.BytesIO(env), io.BytesIO(self.template_a),
+                                io.BytesIO(self.template_a)]
 
         files, env_dict = template_utils.process_environment_and_files(
             url)
@@ -197,12 +197,12 @@ class ShellEnvironmentTest(testtools.TestCase):
             mock.call(tmpl_url)
         ])
 
-    @mock.patch('six.moves.urllib.request.urlopen')
+    @mock.patch('urllib.request.urlopen')
     def test_process_environment_empty_file(self, mock_url):
 
         env_file = '/home/my/dir/env.yaml'
         env = b''
-        mock_url.return_value = six.BytesIO(env)
+        mock_url.return_value = io.BytesIO(env)
 
         files, env_dict = template_utils.process_environment_and_files(
             env_file)
@@ -216,7 +216,7 @@ class ShellEnvironmentTest(testtools.TestCase):
         self.assertEqual({}, env)
         self.assertEqual({}, files)
 
-    @mock.patch('six.moves.urllib.request.urlopen')
+    @mock.patch('urllib.request.urlopen')
     def test_process_multiple_environments_and_files(self, mock_url):
 
         env_file1 = '/home/my/dir/env1.yaml'
@@ -235,12 +235,12 @@ class ShellEnvironmentTest(testtools.TestCase):
           "OS::Thingy2": "file:///home/b/b.yaml"
         '''
 
-        mock_url.side_effect = [six.BytesIO(env1),
-                                six.BytesIO(self.template_a),
-                                six.BytesIO(self.template_a),
-                                six.BytesIO(env2),
-                                six.BytesIO(self.template_a),
-                                six.BytesIO(self.template_a)]
+        mock_url.side_effect = [io.BytesIO(env1),
+                                io.BytesIO(self.template_a),
+                                io.BytesIO(self.template_a),
+                                io.BytesIO(env2),
+                                io.BytesIO(self.template_a),
+                                io.BytesIO(self.template_a)]
 
         files, env = template_utils.process_multiple_environments_and_files(
             [env_file1, env_file2])
@@ -267,7 +267,7 @@ class ShellEnvironmentTest(testtools.TestCase):
             mock.call('file:///home/b/b.yaml')
         ])
 
-    @mock.patch('six.moves.urllib.request.urlopen')
+    @mock.patch('urllib.request.urlopen')
     def test_process_multiple_environments_default_resources(self, mock_url):
 
         env_file1 = '/home/my/dir/env1.yaml'
@@ -289,16 +289,16 @@ class ShellEnvironmentTest(testtools.TestCase):
             resource2:
               "OS::Thingy4": "file:///home/b/b.yaml"
         '''
-        mock_url.side_effect = [six.BytesIO(env1),
-                                six.BytesIO(self.template_a),
-                                six.BytesIO(self.template_a),
-                                six.BytesIO(self.template_a),
-                                six.BytesIO(self.template_a),
-                                six.BytesIO(env2),
-                                six.BytesIO(self.template_a),
-                                six.BytesIO(self.template_a),
-                                six.BytesIO(self.template_a),
-                                six.BytesIO(self.template_a)]
+        mock_url.side_effect = [io.BytesIO(env1),
+                                io.BytesIO(self.template_a),
+                                io.BytesIO(self.template_a),
+                                io.BytesIO(self.template_a),
+                                io.BytesIO(self.template_a),
+                                io.BytesIO(env2),
+                                io.BytesIO(self.template_a),
+                                io.BytesIO(self.template_a),
+                                io.BytesIO(self.template_a),
+                                io.BytesIO(self.template_a)]
 
         files, env = template_utils.process_multiple_environments_and_files(
             [env_file1, env_file2])
@@ -378,7 +378,7 @@ class ShellEnvironmentTest(testtools.TestCase):
         self.assertEqual(self.template_a.decode('utf-8'),
                          files['http://no.where/path/to/b/a.yaml'])
 
-    @mock.patch('six.moves.urllib.request.urlopen')
+    @mock.patch('urllib.request.urlopen')
     def test_process_multiple_environments_and_files_tracker(self, mock_url):
         # Setup
         env_file1 = '/home/my/dir/env1.yaml'
@@ -389,9 +389,9 @@ class ShellEnvironmentTest(testtools.TestCase):
         resource_registry:
           "OS::Thingy1": "file:///home/b/a.yaml"
         '''
-        mock_url.side_effect = [six.BytesIO(env1),
-                                six.BytesIO(self.template_a),
-                                six.BytesIO(self.template_a)]
+        mock_url.side_effect = [io.BytesIO(env1),
+                                io.BytesIO(self.template_a),
+                                io.BytesIO(self.template_a)]
 
         # Test
         env_file_list = []
@@ -419,7 +419,7 @@ class ShellEnvironmentTest(testtools.TestCase):
 
         ])
 
-    @mock.patch('six.moves.urllib.request.urlopen')
+    @mock.patch('urllib.request.urlopen')
     def test_process_environment_relative_file_tracker(self, mock_url):
 
         env_file = '/home/my/dir/env.yaml'
@@ -428,9 +428,9 @@ class ShellEnvironmentTest(testtools.TestCase):
         resource_registry:
           "OS::Thingy": a.yaml
         '''
-        mock_url.side_effect = [six.BytesIO(env),
-                                six.BytesIO(self.template_a),
-                                six.BytesIO(self.template_a)]
+        mock_url.side_effect = [io.BytesIO(env),
+                                io.BytesIO(self.template_a),
+                                io.BytesIO(self.template_a)]
 
         self.assertEqual(
             env_url,
@@ -460,7 +460,7 @@ class ShellEnvironmentTest(testtools.TestCase):
 
         ])
 
-    @mock.patch('six.moves.urllib.request.urlopen')
+    @mock.patch('urllib.request.urlopen')
     def test_process_multiple_environments_empty_registry(self, mock_url):
         # Setup
         env_file1 = '/home/my/dir/env1.yaml'
@@ -473,10 +473,10 @@ class ShellEnvironmentTest(testtools.TestCase):
         env2 = b'''
         resource_registry:
         '''
-        mock_url.side_effect = [six.BytesIO(env1),
-                                six.BytesIO(self.template_a),
-                                six.BytesIO(self.template_a),
-                                six.BytesIO(env2)]
+        mock_url.side_effect = [io.BytesIO(env1),
+                                io.BytesIO(self.template_a),
+                                io.BytesIO(self.template_a),
+                                io.BytesIO(env2)]
 
         # Test
         env_file_list = []
@@ -654,11 +654,11 @@ class TestGetTemplateContents(testtools.TestCase):
                 matchers.MatchesRegex(
                     'Error parsing template file://%s ' % tmpl_file.name))
 
-    @mock.patch('six.moves.urllib.request.urlopen')
+    @mock.patch('urllib.request.urlopen')
     def test_get_template_contents_url(self, mock_url):
         tmpl = b'{"AWSTemplateFormatVersion" : "2010-09-09", "foo": "bar"}'
         url = 'http://no.where/path/to/a.yaml'
-        mock_url.return_value = six.BytesIO(tmpl)
+        mock_url.return_value = io.BytesIO(tmpl)
 
         files, tmpl_parsed = template_utils.get_template_contents(
             template_url=url)
@@ -726,9 +726,9 @@ class TestGetTemplateContents(testtools.TestCase):
                         [{'path': '/tmp/%s' % filename,
                           'content': {'get_file': url},
                           'encoding': 'b64'}]}}}}}
-        with mock.patch('six.moves.urllib.request.urlopen') as mock_url:
+        with mock.patch('urllib.request.urlopen') as mock_url:
             raw_content = base64.decode_as_bytes(content)
-            response = six.BytesIO(raw_content)
+            response = io.BytesIO(raw_content)
             mock_url.return_value = response
             files = {}
             template_utils.resolve_template_get_files(
@@ -746,13 +746,7 @@ ABOkDAABQSwUGAAAAAAEAAQBOAAAARwAAAAAA\n'''
         # zip has '\0' in stream
         self.assertIn(b'\0', base64.decode_as_bytes(content))
         decoded_content = base64.decode_as_bytes(content)
-        if six.PY3:
-            self.assertRaises(UnicodeDecodeError, decoded_content.decode)
-        else:
-            self.assertRaises(
-                UnicodeDecodeError,
-                json.dumps,
-                {'content': decoded_content})
+        self.assertRaises(UnicodeDecodeError, decoded_content.decode)
         self.check_non_utf8_content(
             filename=filename, content=content)
 
@@ -762,13 +756,7 @@ ABOkDAABQSwUGAAAAAAEAAQBOAAAARwAAAAAA\n'''
         # utf6 has '\0' in stream
         self.assertIn(b'\0', base64.decode_as_bytes(content))
         decoded_content = base64.decode_as_bytes(content)
-        if six.PY3:
-            self.assertRaises(UnicodeDecodeError, decoded_content.decode)
-        else:
-            self.assertRaises(
-                UnicodeDecodeError,
-                json.dumps,
-                {'content': decoded_content})
+        self.assertRaises(UnicodeDecodeError, decoded_content.decode)
         self.check_non_utf8_content(filename=filename, content=content)
 
     def test_get_gb18030_content(self):
@@ -777,17 +765,11 @@ ABOkDAABQSwUGAAAAAAEAAQBOAAAARwAAAAAA\n'''
         # gb18030 has no '\0' in stream
         self.assertNotIn('\0', base64.decode_as_bytes(content))
         decoded_content = base64.decode_as_bytes(content)
-        if six.PY3:
-            self.assertRaises(UnicodeDecodeError, decoded_content.decode)
-        else:
-            self.assertRaises(
-                UnicodeDecodeError,
-                json.dumps,
-                {'content': decoded_content})
+        self.assertRaises(UnicodeDecodeError, decoded_content.decode)
         self.check_non_utf8_content(filename=filename, content=content)
 
 
-@mock.patch('six.moves.urllib.request.urlopen')
+@mock.patch('urllib.request.urlopen')
 class TestTemplateGetFileFunctions(testtools.TestCase):
 
     hot_template = b'''heat_template_version: 2013-05-23
@@ -815,12 +797,12 @@ resources:
 
         tmpl_file = '/home/my/dir/template.yaml'
         url = 'file:///home/my/dir/template.yaml'
-        mock_url.side_effect = [six.BytesIO(self.hot_template),
-                                six.BytesIO(b'bar contents'),
-                                six.BytesIO(b'foo contents'),
-                                six.BytesIO(b'baz1 contents'),
-                                six.BytesIO(b'baz2 contents'),
-                                six.BytesIO(b'baz3 contents')]
+        mock_url.side_effect = [io.BytesIO(self.hot_template),
+                                io.BytesIO(b'bar contents'),
+                                io.BytesIO(b'foo contents'),
+                                io.BytesIO(b'baz1 contents'),
+                                io.BytesIO(b'baz2 contents'),
+                                io.BytesIO(b'baz3 contents')]
 
         files, tmpl_parsed = template_utils.get_template_contents(
             template_file=tmpl_file)
@@ -869,8 +851,8 @@ outputs:\n\
   contents:\n\
     value:\n\
       get_file: foo.yaml\n'''
-        mock_url.side_effect = [six.BytesIO(contents),
-                                six.BytesIO(b'foo contents')]
+        mock_url.side_effect = [io.BytesIO(contents),
+                                io.BytesIO(b'foo contents')]
         files = template_utils.get_template_contents(
             template_file=tmpl_file)[0]
         self.assertEqual({foo_url: b'foo contents'}, files)
@@ -892,8 +874,8 @@ outputs:\n\
   template:\n\
     value:\n\
       get_file: foo.yaml\n'''
-        mock_url.side_effect = [six.BytesIO(contents),
-                                six.BytesIO(b'foo contents')]
+        mock_url.side_effect = [io.BytesIO(contents),
+                                io.BytesIO(b'foo contents')]
         # asserts that is fetched only once even though it is
         # referenced in the template twice
         files = template_utils.get_template_contents(
@@ -935,18 +917,18 @@ parameters:
     type: string
     '''
 
-    @mock.patch('six.moves.urllib.request.urlopen')
+    @mock.patch('urllib.request.urlopen')
     def test_hot_template(self, mock_url):
         tmpl_file = '/home/my/dir/template.yaml'
         url = 'file:///home/my/dir/template.yaml'
 
         def side_effect(args):
             if url == args:
-                return six.BytesIO(self.hot_template)
+                return io.BytesIO(self.hot_template)
             if 'file:///home/my/dir/foo.yaml' == args:
-                return six.BytesIO(self.foo_template)
+                return io.BytesIO(self.foo_template)
             if 'file:///home/my/dir/spam/egg.yaml' == args:
-                return six.BytesIO(self.egg_template)
+                return io.BytesIO(self.egg_template)
         mock_url.side_effect = side_effect
 
         files, tmpl_parsed = template_utils.get_template_contents(
@@ -1013,7 +995,7 @@ parameters:
     type: string
     '''
 
-    @mock.patch('six.moves.urllib.request.urlopen')
+    @mock.patch('urllib.request.urlopen')
     def test_hot_template(self, mock_url):
         tmpl_file = '/home/my/dir/template.yaml'
         url = 'file:///home/my/dir/template.yaml'
@@ -1022,11 +1004,11 @@ parameters:
 
         def side_effect(args):
             if url == args:
-                return six.BytesIO(self.hot_template)
+                return io.BytesIO(self.hot_template)
             if foo_url == args:
-                return six.BytesIO(self.foo_template)
+                return io.BytesIO(self.foo_template)
             if bar_url == args:
-                return six.BytesIO(self.bar_template)
+                return io.BytesIO(self.bar_template)
         mock_url.side_effect = side_effect
 
         files, tmpl_parsed = template_utils.get_template_contents(
@@ -1112,7 +1094,7 @@ parameters:
     type: string
     '''
 
-    @mock.patch('six.moves.urllib.request.urlopen')
+    @mock.patch('urllib.request.urlopen')
     def test_env_nested_includes(self, mock_url):
         env_file = '/home/my/dir/env.yaml'
         env_url = 'file:///home/my/dir/env.yaml'
@@ -1130,21 +1112,21 @@ parameters:
 
         def side_effect(args):
             if env_url == args:
-                return six.BytesIO(env)
+                return io.BytesIO(env)
             if template_url == args:
-                return six.BytesIO(self.hot_template)
+                return io.BytesIO(self.hot_template)
             if foo_url == args:
-                return six.BytesIO(self.foo_template)
+                return io.BytesIO(self.foo_template)
             if egg_url == args:
-                return six.BytesIO(self.egg_template)
+                return io.BytesIO(self.egg_template)
             if ham_url == args:
-                return six.BytesIO(b'ham contents')
+                return io.BytesIO(b'ham contents')
             if one_url == args:
-                return six.BytesIO(self.foo_template)
+                return io.BytesIO(self.foo_template)
             if two_url == args:
-                return six.BytesIO(self.foo_template)
+                return io.BytesIO(self.foo_template)
             if three_url == args:
-                return six.BytesIO(b'three contents')
+                return io.BytesIO(b'three contents')
         mock_url.side_effect = side_effect
 
         files, env_dict = template_utils.process_environment_and_files(
diff --git a/heatclient/v1/events.py b/heatclient/v1/events.py
index f86549d..9427691 100644
--- a/heatclient/v1/events.py
+++ b/heatclient/v1/events.py
@@ -15,7 +15,7 @@
 
 import collections
 from oslo_utils import encodeutils
-from six.moves.urllib import parse
+from urllib import parse
 
 from heatclient.common import base
 from heatclient.common import utils
diff --git a/heatclient/v1/resource_types.py b/heatclient/v1/resource_types.py
index b226541..4073dc1 100644
--- a/heatclient/v1/resource_types.py
+++ b/heatclient/v1/resource_types.py
@@ -12,8 +12,7 @@
 #    under the License.
 
 from oslo_utils import encodeutils
-import six
-from six.moves.urllib import parse
+from urllib import parse
 
 from heatclient.common import base
 from heatclient.common import utils
@@ -21,7 +20,7 @@ from heatclient.common import utils
 
 class ResourceType(base.Resource):
     def __repr__(self):
-        if isinstance(self._info, six.string_types):
+        if isinstance(self._info, str):
             return "<ResourceType %s>" % self._info
         else:
             return "<ResourceType %s>" % self._info.get('resource_type')
@@ -30,7 +29,7 @@ class ResourceType(base.Resource):
         return self.manager.data(self, **kwargs)
 
     def _add_details(self, info):
-        if isinstance(info, six.string_types):
+        if isinstance(info, str):
             self.resource_type = info
         elif isinstance(info, dict):
             self.resource_type = info.get('resource_type')
diff --git a/heatclient/v1/resources.py b/heatclient/v1/resources.py
index cfb3203..1054986 100644
--- a/heatclient/v1/resources.py
+++ b/heatclient/v1/resources.py
@@ -14,7 +14,7 @@
 #    under the License.
 
 from oslo_utils import encodeutils
-from six.moves.urllib import parse
+from urllib import parse
 
 from heatclient.common import base
 from heatclient.common import utils
diff --git a/heatclient/v1/shell.py b/heatclient/v1/shell.py
index ce6272b..98deb97 100644
--- a/heatclient/v1/shell.py
+++ b/heatclient/v1/shell.py
@@ -18,8 +18,7 @@ import sys
 
 from oslo_serialization import jsonutils
 from oslo_utils import strutils
-import six
-from six.moves.urllib import request
+from urllib import request
 import yaml
 
 from heatclient._i18n import _
@@ -306,7 +305,7 @@ def do_stack_delete(hc, args):
 
     try:
         if not args.yes and sys.stdin.isatty():
-            prompt_response = six.moves.input(
+            prompt_response = input(
                 _("Are you sure you want to delete this stack(s) [y/N]? ")
             ).lower()
             if not prompt_response.startswith('y'):
@@ -542,7 +541,7 @@ def do_stack_update(hc, args):
         try:
             rollback = strutils.bool_from_string(args.rollback, strict=True)
         except ValueError as ex:
-            raise exc.CommandError(six.text_type(ex))
+            raise exc.CommandError(str(ex))
         else:
             fields['disable_rollback'] = not(rollback)
     # TODO(pshchelo): remove the following 'else' clause after deprecation
@@ -1067,7 +1066,7 @@ def do_resource_signal(hc, args):
         data_url = utils.normalise_file_path_to_url(data_file)
         data = request.urlopen(data_url).read()
     if data:
-        if isinstance(data, six.binary_type):
+        if isinstance(data, bytes):
             data = data.decode('utf-8')
         try:
             data = jsonutils.loads(data)
diff --git a/heatclient/v1/software_configs.py b/heatclient/v1/software_configs.py
index 8d5c9e1..5e9a452 100644
--- a/heatclient/v1/software_configs.py
+++ b/heatclient/v1/software_configs.py
@@ -10,7 +10,7 @@
 # License for the specific language governing permissions and limitations
 # under the License.
 
-from six.moves.urllib import parse
+from urllib import parse
 
 from heatclient.common import base
 from heatclient.common import utils
diff --git a/heatclient/v1/software_deployments.py b/heatclient/v1/software_deployments.py
index 966838d..4422dd9 100644
--- a/heatclient/v1/software_deployments.py
+++ b/heatclient/v1/software_deployments.py
@@ -10,7 +10,7 @@
 # License for the specific language governing permissions and limitations
 # under the License.
 
-from six.moves.urllib import parse
+from urllib import parse
 
 from heatclient.common import base
 from heatclient.common import utils
diff --git a/heatclient/v1/stacks.py b/heatclient/v1/stacks.py
index d1acfa5..a303e63 100644
--- a/heatclient/v1/stacks.py
+++ b/heatclient/v1/stacks.py
@@ -13,7 +13,7 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
-from six.moves.urllib import parse
+from urllib import parse
 
 from heatclient._i18n import _
 from heatclient.common import base
diff --git a/heatclient/v1/template_versions.py b/heatclient/v1/template_versions.py
index 2dab4ad..fe1b12f 100644
--- a/heatclient/v1/template_versions.py
+++ b/heatclient/v1/template_versions.py
@@ -12,7 +12,7 @@
 #    under the License.
 
 from oslo_utils import encodeutils
-from six.moves.urllib import parse
+from urllib import parse
 
 from heatclient.common import base
 
diff --git a/lower-constraints.txt b/lower-constraints.txt
index 41688ef..47d818a 100644
--- a/lower-constraints.txt
+++ b/lower-constraints.txt
@@ -76,7 +76,6 @@ requests==2.14.2
 requestsexceptions==1.2.0
 rfc3986==0.3.1
 simplejson==3.5.1
-six==1.10.0
 snowballstemmer==1.2.1
 stestr==2.0.0
 stevedore==1.20.0
diff --git a/requirements.txt b/requirements.txt
index 3874e36..2554cdd 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -15,4 +15,3 @@ keystoneauth1>=3.8.0 # Apache-2.0
 python-swiftclient>=3.2.0 # Apache-2.0
 PyYAML>=3.13 # MIT
 requests>=2.14.2 # Apache-2.0
-six>=1.10.0 # MIT