Merge commit for internal changes.

24 files changed, 211 insertions, 286 deletions

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 0cdfa92..7b41a67 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -6,7 +6,9 @@ The format is based on [Keep a Changelog](https://keepachangelog.com).
 
 ## Unreleased
 
-Nothing notable unreleased.
+*   `Flag` instances now raise an error if used in a bool context. This prevents
+    the occasional mistake of testing an instance for truthiness rather than
+    testing `flag.value`.
 
 ## 1.0.0 (2021-11-09)
 
diff --git a/WORKSPACE b/WORKSPACE
index 5397414..1370aae 100644
--- a/WORKSPACE
+++ b/WORKSPACE
@@ -17,22 +17,11 @@ load("@bazel_tools//tools/build_defs/repo:http.bzl", "http_archive")
 
 http_archive(
     name = "six_archive",
-    urls = [
-        "http://mirror.bazel.build/pypi.python.org/packages/source/s/six/six-1.10.0.tar.gz",
-        "https://pypi.python.org/packages/source/s/six/six-1.10.0.tar.gz",
-    ],
+    build_file = "@//third_party:six.BUILD",
     sha256 = "105f8d68616f8248e24bf0e9372ef04d3cc10104f1980f54d57b2ce73a5ad56a",
     strip_prefix = "six-1.10.0",
-    build_file = "@//third_party:six.BUILD",
-)
-
-http_archive(
-    name = "mock_archive",
     urls = [
-        "http://mirror.bazel.build/pypi.python.org/packages/a2/52/7edcd94f0afb721a2d559a5b9aae8af4f8f2c79bc63fdbe8a8a6c9b23bbe/mock-1.0.1.tar.gz",
-        "https://pypi.python.org/packages/a2/52/7edcd94f0afb721a2d559a5b9aae8af4f8f2c79bc63fdbe8a8a6c9b23bbe/mock-1.0.1.tar.gz",
+        "http://mirror.bazel.build/pypi.python.org/packages/source/s/six/six-1.10.0.tar.gz",
+        "https://pypi.python.org/packages/source/s/six/six-1.10.0.tar.gz",
     ],
-    sha256 = "b839dd2d9c117c701430c149956918a423a9863b48b09c90e30a6013e7d2f44f",
-    strip_prefix = "mock-1.0.1",
-    build_file = "@//third_party:mock.BUILD",
 )
diff --git a/absl/BUILD b/absl/BUILD
index c83ab28..496b0e3 100644
--- a/absl/BUILD
+++ b/absl/BUILD
@@ -76,7 +76,6 @@ py_test(
     deps = [
         ":command_name",
         "//absl/testing:absltest",
-        "@mock_archive//:mock",
     ],
 )
 
diff --git a/absl/flags/BUILD b/absl/flags/BUILD
index d54af1d..c180599 100644
--- a/absl/flags/BUILD
+++ b/absl/flags/BUILD
@@ -1,4 +1,4 @@
-licenses(["notice"])  # Apache 2.0
+licenses(["notice"])
 
 py_library(
     name = "flags",
@@ -256,7 +256,6 @@ py_test(
         ":_validators",
         ":flags",
         "//absl/testing:absltest",
-        "@mock_archive//:mock",
     ],
 )
 
diff --git a/absl/flags/_defines.py b/absl/flags/_defines.py
index f655714..4494c3b 100644
--- a/absl/flags/_defines.py
+++ b/absl/flags/_defines.py
@@ -798,7 +798,7 @@ def DEFINE_multi_enum(  # pylint: disable=invalid-name,redefined-builtin
       serializer,
       name,
       default,
-      help,
+      '<%s>: %s' % ('|'.join(enum_values), help),
       flag_values,
       required=required,
       **args)
diff --git a/absl/flags/_flag.py b/absl/flags/_flag.py
index a893b22..a1c53ff 100644
--- a/absl/flags/_flag.py
+++ b/absl/flags/_flag.py
@@ -128,6 +128,10 @@ class Flag(object):
       return id(self) < id(other)
     return NotImplemented
 
+  def __bool__(self):
+    raise TypeError('A Flag instance would always be True. '
+                    'Did you mean to test the `.value` attribute?')
+
   def __getstate__(self):
     raise TypeError("can't pickle Flag objects")
 
diff --git a/absl/flags/_flagvalues.py b/absl/flags/_flagvalues.py
index dab6091..c9be720 100644
--- a/absl/flags/_flagvalues.py
+++ b/absl/flags/_flagvalues.py
@@ -774,7 +774,7 @@ class FlagValues(object):
         continue
 
       flag = flag_dict.get(name)
-      if flag:
+      if flag is not None:
         if flag.boolean and value is None:
           value = 'true'
         else:
@@ -782,13 +782,13 @@ class FlagValues(object):
       elif name.startswith('no') and len(name) > 2:
         # Boolean flags can take the form of --noflag, with no value.
         noflag = flag_dict.get(name[2:])
-        if noflag and noflag.boolean:
+        if noflag is not None and noflag.boolean:
           if value is not None:
             raise ValueError(arg + ' does not take an argument')
           flag = noflag
           value = 'false'
 
-      if retired_flag_func and not flag:
+      if retired_flag_func and flag is None:
         is_retired, is_bool = retired_flag_func(name)
 
         # If we didn't recognize that flag, but it starts with
@@ -808,7 +808,7 @@ class FlagValues(object):
               'be specified. See go/totw/90.', name)
           continue
 
-      if flag:
+      if flag is not None:
         flag.parse(value)
         flag.using_default_value = False
       else:
diff --git a/absl/flags/tests/_flag_test.py b/absl/flags/tests/_flag_test.py
index 800a00c..492f117 100644
--- a/absl/flags/tests/_flag_test.py
+++ b/absl/flags/tests/_flag_test.py
@@ -35,6 +35,7 @@ from absl.testing import parameterized
 class FlagTest(absltest.TestCase):
 
   def setUp(self):
+    super().setUp()
     self.flag = _flag.Flag(
         _argument_parser.ArgumentParser(),
         _argument_parser.ArgumentSerializer(),
@@ -59,6 +60,11 @@ class FlagTest(absltest.TestCase):
         'number', 1, 'help')
     self.assertEqual(1, flag.default_unparsed)
 
+  def test_no_truthiness(self):
+    with self.assertRaises(TypeError):
+      if self.flag:
+        self.fail('Flag instances must raise rather than be truthy.')
+
   def test_set_default_overrides_current_value(self):
     self.assertEqual('apple', self.flag.value)
     self.flag._set_default('orange')
@@ -71,14 +77,14 @@ class FlagTest(absltest.TestCase):
     self.assertEqual('apple', self.flag.value)
 
   def test_pickle(self):
-    with self.assertRaisesRegexp(TypeError, "can't pickle Flag objects"):
+    with self.assertRaisesRegex(TypeError, "can't pickle Flag objects"):
       pickle.dumps(self.flag)
 
   def test_copy(self):
     self.flag.value = 'orange'
 
-    with self.assertRaisesRegexp(
-        TypeError, 'Flag does not support shallow copies'):
+    with self.assertRaisesRegex(TypeError,
+                                'Flag does not support shallow copies'):
       copy.copy(self.flag)
 
     flag2 = copy.deepcopy(self.flag)
@@ -172,10 +178,10 @@ class EnumClassFlagTest(parameterized.TestCase):
 class MultiEnumClassFlagTest(parameterized.TestCase):
 
   @parameterized.named_parameters(
-      ('NoHelpSupplied', '', '<apple|orange>: (no help available);\n    '
+      ('NoHelpSupplied', '', '<apple|orange>: (no help available);\n    ' +
        'repeat this option to specify a list of values', False),
       ('WithHelpSupplied', 'Type of fruit.',
-       '<APPLE|ORANGE>: Type of fruit.;\n    '
+       '<APPLE|ORANGE>: Type of fruit.;\n    ' +
        'repeat this option to specify a list of values', True))
   def test_help_text(self, helptext_input, helptext_output, case_sensitive):
     f = _flag.MultiEnumClassFlag(
diff --git a/absl/flags/tests/flags_helpxml_test.py b/absl/flags/tests/flags_helpxml_test.py
index 424c3dd..e2168ac 100644
--- a/absl/flags/tests/flags_helpxml_test.py
+++ b/absl/flags/tests/flags_helpxml_test.py
@@ -340,7 +340,7 @@ class FlagCreateXMLDOMElement(absltest.TestCase):
         '<flag>\n'
         '  <file>tool</file>\n'
         '  <name>flavours</name>\n'
-        '  <meaning>Compilation flavour.;\n'
+        '  <meaning>&lt;APPLE|BANANA|CHERRY&gt;: Compilation flavour.;\n'
         '    repeat this option to specify a list of values</meaning>\n'
         '  <default>[\'APPLE\', \'BANANA\']</default>\n'
         '  <current>[\'APPLE\', \'BANANA\']</current>\n'
@@ -474,7 +474,7 @@ EXPECTED_HELP_XML_FOR_FLAGS_FROM_MAIN_MODULE = """\
     <key>yes</key>
     <file>%(main_module_name)s</file>
     <name>flavours</name>
-    <meaning>Compilation flavour.;
+    <meaning>&lt;APPLE|BANANA|CHERRY&gt;: Compilation flavour.;
     repeat this option to specify a list of values</meaning>
     <default>['APPLE', 'BANANA']</default>
     <current>['APPLE', 'BANANA']</current>
diff --git a/absl/flags/tests/flags_numeric_bounds_test.py b/absl/flags/tests/flags_numeric_bounds_test.py
index 5743258..d3c2a95 100644
--- a/absl/flags/tests/flags_numeric_bounds_test.py
+++ b/absl/flags/tests/flags_numeric_bounds_test.py
@@ -14,14 +14,10 @@
 
 """Tests for lower/upper bounds validators for numeric flags."""
 
-from __future__ import absolute_import
-from __future__ import division
-from __future__ import print_function
-
+from unittest import mock
 from absl import flags
 from absl.flags import _validators
 from absl.testing import absltest
-import mock
 
 
 class NumericFlagBoundsTest(absltest.TestCase):
diff --git a/absl/flags/tests/flags_test.py b/absl/flags/tests/flags_test.py
index 75a61d5..8a42bc9 100644
--- a/absl/flags/tests/flags_test.py
+++ b/absl/flags/tests/flags_test.py
@@ -1511,6 +1511,20 @@ class MultiEnumFlagsTest(absltest.TestCase):
     fv(argv)
     self.assertListEqual(fv.get_flag_value('m_enum', None), ['WHOOSH', 'FOO'])
 
+  def test_help_text(self):
+    """Test multi_enum flag's help text."""
+    fv = flags.FlagValues()
+
+    flags.DEFINE_multi_enum(
+        'm_enum',
+        None, ['FOO', 'BAR'],
+        'Enum option that can occur multiple times',
+        flag_values=fv)
+    self.assertRegex(
+        fv['m_enum'].help,
+        r'<FOO\|BAR>: Enum option that can occur multiple times;\s+'
+        'repeat this option to specify a list of values')
+
   def test_single_value_default(self):
     """Test multi_enum flags with a single default value."""
     fv = flags.FlagValues()
@@ -1590,6 +1604,21 @@ class MultiEnumClassFlagsTest(absltest.TestCase):
 
     self.assertIsNone(fv.fruit)
 
+  def test_help_text(self):
+    fv = flags.FlagValues()
+    enum_defaults = None
+    flags.DEFINE_multi_enum_class(
+        'fruit',
+        enum_defaults,
+        Fruit,
+        'Enum option that can occur multiple times',
+        flag_values=fv)
+
+    self.assertRegex(
+        fv['fruit'].help,
+        r'<apple\|orange>: Enum option that can occur multiple times;\s+'
+        'repeat this option to specify a list of values')
+
   def test_define_results_in_registered_flag_with_string(self):
     fv = flags.FlagValues()
     enum_defaults = 'apple'
diff --git a/absl/logging/BUILD b/absl/logging/BUILD
index d83a2b6..e666d7a 100644
--- a/absl/logging/BUILD
+++ b/absl/logging/BUILD
@@ -1,4 +1,4 @@
-licenses(["notice"])  # Apache 2.0
+licenses(["notice"])
 
 py_library(
     name = "logging",
@@ -9,7 +9,6 @@ py_library(
         ":converter",
         "//absl:_collections_abc",
         "//absl/flags",
-        "@six_archive//:six",
     ],
 )
 
@@ -57,7 +56,6 @@ py_test(
     deps = [
         ":logging",
         "//absl/testing:absltest",
-        "@mock_archive//:mock",
     ],
 )
 
diff --git a/absl/logging/__init__.py b/absl/logging/__init__.py
index c79643f..a475bd5 100644
--- a/absl/logging/__init__.py
+++ b/absl/logging/__init__.py
@@ -71,10 +71,6 @@ program.
 The differences in behavior are historical and unfortunate.
 """
 
-from __future__ import absolute_import
-from __future__ import division
-from __future__ import print_function
-
 import collections
 import getpass
 import io
@@ -84,6 +80,7 @@ import os
 import socket
 import struct
 import sys
+import threading
 import time
 import timeit
 import traceback
@@ -93,12 +90,6 @@ import warnings
 from absl import flags
 from absl._collections_abc import abc
 from absl.logging import converter
-import six
-
-if six.PY2:
-  import thread as _thread_lib  # For .get_ident().
-else:
-  import threading as _thread_lib  # For .get_ident().
 
 try:
   from typing import NoReturn
@@ -257,7 +248,7 @@ class _LoggerLevelsSerializer(object):
   """Serializer for --logger_levels flag."""
 
   def serialize(self, value):
-    if isinstance(value, six.string_types):
+    if isinstance(value, str):
       return value
     return ','.join(
         '{}:{}'.format(name, level) for name, level in value.items())
@@ -399,15 +390,11 @@ def warning(msg, *args, **kwargs):
   log(WARNING, msg, *args, **kwargs)
 
 
-if six.PY2:
-  warn = warning  # Deprecated function.
-else:
-
-  def warn(msg, *args, **kwargs):
-    """Deprecated, use 'warning' instead."""
-    warnings.warn("The 'warn' function is deprecated, use 'warning' instead",
-                  DeprecationWarning, 2)
-    log(WARNING, msg, *args, **kwargs)
+def warn(msg, *args, **kwargs):
+  """Deprecated, use 'warning' instead."""
+  warnings.warn("The 'warn' function is deprecated, use 'warning' instead",
+                DeprecationWarning, 2)
+  log(WARNING, msg, *args, **kwargs)
 
 
 def info(msg, *args, **kwargs):
@@ -729,8 +716,7 @@ def find_log_dir(log_dir=None):
   for d in dirs:
     if os.path.isdir(d) and os.access(d, os.W_OK):
       return d
-  exception_class = OSError if six.PY2 else FileNotFoundError
-  raise exception_class(
+  raise FileNotFoundError(
       "Can't find a writable directory for logs, tried %s" % dirs)
 
 
@@ -795,7 +781,7 @@ def skip_log_prefix(func):
     file_name = func_code.co_filename
     func_name = func_code.co_name
     func_lineno = func_code.co_firstlineno
-  elif isinstance(func, six.string_types):
+  elif isinstance(func, str):
     file_name = get_absl_logger().findCaller()[0]
     func_name = func
     func_lineno = None
@@ -839,10 +825,7 @@ class PythonHandler(logging.StreamHandler):
         os.getpid())
     filename = os.path.join(actual_log_dir, basename)
 
-    if six.PY2:
-      self.stream = open(filename, 'a')
-    else:
-      self.stream = open(filename, 'a', encoding='utf-8')
+    self.stream = open(filename, 'a', encoding='utf-8')
 
     # os.symlink is not available on Windows Python 2.
     if getattr(os, 'symlink', None):
@@ -1072,16 +1055,13 @@ class ABSLLogger(logging.getLoggerClass()):
           (code.co_filename, code.co_name,
            code.co_firstlineno) not in f_to_skip and
           (code.co_filename, code.co_name) not in f_to_skip):
-        if six.PY2 and not stack_info:
-          return (code.co_filename, frame.f_lineno, code.co_name)
-        else:
-          sinfo = None
-          if stack_info:
-            out = io.StringIO()
-            out.write(u'Stack (most recent call last):\n')
-            traceback.print_stack(frame, file=out)
-            sinfo = out.getvalue().rstrip(u'\n')
-          return (code.co_filename, frame.f_lineno, code.co_name, sinfo)
+        sinfo = None
+        if stack_info:
+          out = io.StringIO()
+          out.write(u'Stack (most recent call last):\n')
+          traceback.print_stack(frame, file=out)
+          sinfo = out.getvalue().rstrip(u'\n')
+        return (code.co_filename, frame.f_lineno, code.co_name, sinfo)
       frame = frame.f_back
 
   def critical(self, msg, *args, **kwargs):
@@ -1098,9 +1078,8 @@ class ABSLLogger(logging.getLoggerClass()):
 
   def warn(self, msg, *args, **kwargs):
     """Logs 'msg % args' with severity 'WARN'."""
-    if six.PY3:
-      warnings.warn("The 'warn' method is deprecated, use 'warning' instead",
-                    DeprecationWarning, 2)
+    warnings.warn("The 'warn' method is deprecated, use 'warning' instead",
+                  DeprecationWarning, 2)
     self.log(logging.WARN, msg, *args, **kwargs)
 
   def warning(self, msg, *args, **kwargs):
@@ -1183,7 +1162,7 @@ def _get_thread_id():
   Returns:
     Thread ID unique to this process (unsigned)
   """
-  thread_id = _thread_lib.get_ident()
+  thread_id = threading.get_ident()
   return thread_id & _THREAD_ID_MASK
 
 
diff --git a/absl/logging/converter.py b/absl/logging/converter.py
index 87f4324..53dd46d 100644
--- a/absl/logging/converter.py
+++ b/absl/logging/converter.py
@@ -43,10 +43,6 @@ representation, before manipulating the levels, and then only to cpp
 or absl if those level schemes are absolutely necessary.
 """
 
-from __future__ import absolute_import
-from __future__ import division
-from __future__ import print_function
-
 import logging
 
 STANDARD_CRITICAL = logging.CRITICAL
diff --git a/absl/logging/tests/log_before_import_test.py b/absl/logging/tests/log_before_import_test.py
index d1ba61f..903af16 100644
--- a/absl/logging/tests/log_before_import_test.py
+++ b/absl/logging/tests/log_before_import_test.py
@@ -14,20 +14,16 @@
 
 """Test of logging behavior before app.run(), aka flag and logging init()."""
 
-from __future__ import absolute_import
-from __future__ import division
-from __future__ import print_function
-
 import contextlib
 import io
 import os
 import re
 import sys
 import tempfile
+from unittest import mock
 
 from absl import logging
 from absl.testing import absltest
-import mock
 
 logging.get_verbosity()  # Access --verbosity before flag parsing.
 # Access --logtostderr before flag parsing.
diff --git a/absl/logging/tests/logging_functional_test.py b/absl/logging/tests/logging_functional_test.py
index faa0de4..98a2fab 100644
--- a/absl/logging/tests/logging_functional_test.py
+++ b/absl/logging/tests/logging_functional_test.py
@@ -324,6 +324,7 @@ class FunctionalTest(parameterized.TestCase):
                  pass_logtostderr=False,
                  use_absl_log_file=False,
                  show_info_prefix=1,
+                 call_dict_config=False,
                  extra_args=()):
     """Execute the helper script and verify its output.
 
@@ -343,6 +344,8 @@ class FunctionalTest(parameterized.TestCase):
           logging.get_absl_handler().use_absl_log_file() before test_fn in
           logging_functional_test_helper.
       show_info_prefix: --showprefixforinfo value passed to the helper script.
+      call_dict_config: True if helper script should call
+          logging.config.dictConfig.
       extra_args: Iterable of str (optional, defaults to ()) - extra arguments
           to pass to the helper script.
 
@@ -361,6 +364,7 @@ class FunctionalTest(parameterized.TestCase):
     env.update({
         'TEST_NAME': test_name,
         'USE_ABSL_LOG_FILE': '%d' % (use_absl_log_file,),
+        'CALL_DICT_CONFIG': '%d' % (call_dict_config,),
     })
     cmd = [self._get_helper()] + args
 
diff --git a/absl/logging/tests/logging_functional_test_helper.py b/absl/logging/tests/logging_functional_test_helper.py
index 0eccc74..b95647b 100644
--- a/absl/logging/tests/logging_functional_test_helper.py
+++ b/absl/logging/tests/logging_functional_test_helper.py
@@ -15,6 +15,7 @@
 """Helper script for logging_functional_test."""
 
 import logging as std_logging
+import logging.config as std_logging_config
 import os
 import sys
 import threading
@@ -306,4 +307,6 @@ def main(argv):
 
 if __name__ == '__main__':
   sys.argv[0] = 'py_argv_0'
+  if os.environ.get('CALL_DICT_CONFIG') == '1':
+    std_logging_config.dictConfig({'version': 1})
   app.run(main)
diff --git a/absl/logging/tests/logging_test.py b/absl/logging/tests/logging_test.py
index c399f37..e5c4fcc 100644
--- a/absl/logging/tests/logging_test.py
+++ b/absl/logging/tests/logging_test.py
@@ -366,6 +366,7 @@ class PythonHandlerTest(absltest.TestCase):
 class ABSLHandlerTest(absltest.TestCase):
 
   def setUp(self):
+    super().setUp()
     formatter = logging.PythonFormatter()
     self.absl_handler = logging.ABSLHandler(formatter)
 
@@ -438,12 +439,14 @@ class ABSLLoggerTest(absltest.TestCase):
     sys._getframe.return_value = mock_frame_0
 
   def setUp(self):
+    super().setUp()
     self.message = 'Hello Nurse'
     self.logger = logging.ABSLLogger('')
 
   def tearDown(self):
     mock.patch.stopall()
     self.logger._frames_to_skip.clear()
+    super().tearDown()
 
   def test_constructor_without_level(self):
     self.logger = logging.ABSLLogger('')
@@ -579,6 +582,7 @@ class ABSLLoggerTest(absltest.TestCase):
 class ABSLLogPrefixTest(parameterized.TestCase):
 
   def setUp(self):
+    super().setUp()
     self.record = std_logging.LogRecord(
         'name', std_logging.INFO, 'path/to/source.py', 13, 'log message',
         None, None)
@@ -804,28 +808,28 @@ class LoggingTest(absltest.TestCase):
     old_level = logging.get_verbosity()
 
     logging.set_verbosity(logging.DEBUG)
-    self.assertEquals(logging.get_verbosity(), logging.DEBUG)
+    self.assertEqual(logging.get_verbosity(), logging.DEBUG)
     self.assertTrue(logging.level_debug())
     self.assertTrue(logging.level_info())
     self.assertTrue(logging.level_warning())
     self.assertTrue(logging.level_error())
 
     logging.set_verbosity(logging.INFO)
-    self.assertEquals(logging.get_verbosity(), logging.INFO)
+    self.assertEqual(logging.get_verbosity(), logging.INFO)
     self.assertFalse(logging.level_debug())
     self.assertTrue(logging.level_info())
     self.assertTrue(logging.level_warning())
     self.assertTrue(logging.level_error())
 
     logging.set_verbosity(logging.WARNING)
-    self.assertEquals(logging.get_verbosity(), logging.WARNING)
+    self.assertEqual(logging.get_verbosity(), logging.WARNING)
     self.assertFalse(logging.level_debug())
     self.assertFalse(logging.level_info())
     self.assertTrue(logging.level_warning())
     self.assertTrue(logging.level_error())
 
     logging.set_verbosity(logging.ERROR)
-    self.assertEquals(logging.get_verbosity(), logging.ERROR)
+    self.assertEqual(logging.get_verbosity(), logging.ERROR)
     self.assertFalse(logging.level_debug())
     self.assertFalse(logging.level_info())
     self.assertTrue(logging.level_error())
@@ -837,43 +841,43 @@ class LoggingTest(absltest.TestCase):
 
     # Lowercase names.
     logging.set_verbosity('debug')
-    self.assertEquals(logging.get_verbosity(), logging.DEBUG)
+    self.assertEqual(logging.get_verbosity(), logging.DEBUG)
     logging.set_verbosity('info')
-    self.assertEquals(logging.get_verbosity(), logging.INFO)
+    self.assertEqual(logging.get_verbosity(), logging.INFO)
     logging.set_verbosity('warning')
-    self.assertEquals(logging.get_verbosity(), logging.WARNING)
+    self.assertEqual(logging.get_verbosity(), logging.WARNING)
     logging.set_verbosity('warn')
-    self.assertEquals(logging.get_verbosity(), logging.WARNING)
+    self.assertEqual(logging.get_verbosity(), logging.WARNING)
     logging.set_verbosity('error')
-    self.assertEquals(logging.get_verbosity(), logging.ERROR)
+    self.assertEqual(logging.get_verbosity(), logging.ERROR)
     logging.set_verbosity('fatal')
 
     # Uppercase names.
-    self.assertEquals(logging.get_verbosity(), logging.FATAL)
+    self.assertEqual(logging.get_verbosity(), logging.FATAL)
     logging.set_verbosity('DEBUG')
-    self.assertEquals(logging.get_verbosity(), logging.DEBUG)
+    self.assertEqual(logging.get_verbosity(), logging.DEBUG)
     logging.set_verbosity('INFO')
-    self.assertEquals(logging.get_verbosity(), logging.INFO)
+    self.assertEqual(logging.get_verbosity(), logging.INFO)
     logging.set_verbosity('WARNING')
-    self.assertEquals(logging.get_verbosity(), logging.WARNING)
+    self.assertEqual(logging.get_verbosity(), logging.WARNING)
     logging.set_verbosity('WARN')
-    self.assertEquals(logging.get_verbosity(), logging.WARNING)
+    self.assertEqual(logging.get_verbosity(), logging.WARNING)
     logging.set_verbosity('ERROR')
-    self.assertEquals(logging.get_verbosity(), logging.ERROR)
+    self.assertEqual(logging.get_verbosity(), logging.ERROR)
     logging.set_verbosity('FATAL')
-    self.assertEquals(logging.get_verbosity(), logging.FATAL)
+    self.assertEqual(logging.get_verbosity(), logging.FATAL)
 
     # Integers as strings.
     logging.set_verbosity(str(logging.DEBUG))
-    self.assertEquals(logging.get_verbosity(), logging.DEBUG)
+    self.assertEqual(logging.get_verbosity(), logging.DEBUG)
     logging.set_verbosity(str(logging.INFO))
-    self.assertEquals(logging.get_verbosity(), logging.INFO)
+    self.assertEqual(logging.get_verbosity(), logging.INFO)
     logging.set_verbosity(str(logging.WARNING))
-    self.assertEquals(logging.get_verbosity(), logging.WARNING)
+    self.assertEqual(logging.get_verbosity(), logging.WARNING)
     logging.set_verbosity(str(logging.ERROR))
-    self.assertEquals(logging.get_verbosity(), logging.ERROR)
+    self.assertEqual(logging.get_verbosity(), logging.ERROR)
     logging.set_verbosity(str(logging.FATAL))
-    self.assertEquals(logging.get_verbosity(), logging.FATAL)
+    self.assertEqual(logging.get_verbosity(), logging.FATAL)
 
     logging.set_verbosity(old_level)
 
diff --git a/absl/testing/BUILD b/absl/testing/BUILD
index de77bcc..6dbbaea 100644
--- a/absl/testing/BUILD
+++ b/absl/testing/BUILD
@@ -1,4 +1,4 @@
-licenses(["notice"])  # Apache 2.0
+licenses(["notice"])
 
 py_library(
     name = "absltest",
@@ -12,7 +12,6 @@ py_library(
         "//absl:app",
         "//absl/flags",
         "//absl/logging",
-        "@six_archive//:six",
     ],
 )
 
@@ -36,7 +35,6 @@ py_library(
     deps = [
         ":absltest",
         "//absl:_collections_abc",
-        "@six_archive//:six",
     ],
 )
 
@@ -47,7 +45,6 @@ py_library(
     visibility = ["//visibility:public"],
     deps = [
         ":_pretty_print_reporter",
-        "@six_archive//:six",
     ],
 )
 
diff --git a/absl/testing/absltest.py b/absl/testing/absltest.py
index 1ade38e..1303fd4 100644
--- a/absl/testing/absltest.py
+++ b/absl/testing/absltest.py
@@ -18,10 +18,6 @@ This module contains base classes and high-level functions for Abseil-style
 tests.
 """
 
-from __future__ import absolute_import
-from __future__ import division
-from __future__ import print_function
-
 import contextlib
 import difflib
 import enum
@@ -43,6 +39,8 @@ import sys
 import tempfile
 import textwrap
 import unittest
+from unittest import mock  # pylint: disable=unused-import Allow absltest.mock.
+from urllib import parse
 
 try:
   # The faulthandler module isn't always available, and pytype doesn't
@@ -60,9 +58,6 @@ from absl import logging
 from absl._collections_abc import abc
 from absl.testing import _pretty_print_reporter
 from absl.testing import xml_reporter
-import six
-from six.moves import urllib
-from six.moves import xrange  # pylint: disable=redefined-builtin
 
 # Make typing an optional import to avoid it being a required dependency
 # in Python 2. Type checkers will still understand the imports.
@@ -84,14 +79,6 @@ else:
     _OutcomeType = unittest.case._Outcome  # pytype: disable=module-attr
 
 
-if six.PY3:
-  from unittest import mock  # pylint: disable=unused-import
-else:
-  try:
-    import mock  # type: ignore
-  except ImportError:
-    mock = None
-
 
 # Re-export a bunch of unittest functions we support so that people don't
 # have to import unittest to get them
@@ -107,7 +94,7 @@ expectedFailure = unittest.expectedFailure
 
 FLAGS = flags.FLAGS
 
-_TEXT_OR_BINARY_TYPES = (six.text_type, six.binary_type)
+_TEXT_OR_BINARY_TYPES = (str, bytes)
 
 # Suppress surplus entries in AssertionError stack traces.
 __unittest = True  # pylint: disable=invalid-name
@@ -296,8 +283,8 @@ def _open(filepath, mode, _open_func=open):
   # type: (Text, Text, Callable[..., IO]) -> IO
   """Opens a file.
 
-  Like open(), but compatible with Python 2 and 3. Also ensures that we can open
-  real files even if tests stub out open().
+  Like open(), but ensure that we can open real files even if tests stub out
+  open().
 
   Args:
     filepath: A filepath.
@@ -307,10 +294,7 @@ def _open(filepath, mode, _open_func=open):
   Returns:
     The opened file object.
   """
-  if six.PY2:
-    return _open_func(filepath, mode)
-  else:
-    return _open_func(filepath, mode, encoding='utf-8')
+  return _open_func(filepath, mode, encoding='utf-8')
 
 
 class _TempDir(object):
@@ -390,7 +374,7 @@ class _TempDir(object):
 
     # Note: there's no need to clear the directory since the containing
     # dir was cleared by the tempdir() function.
-    _makedirs_exist_ok(path)
+    os.makedirs(path, exist_ok=True)
     return _TempDir(path)
 
 
@@ -418,14 +402,14 @@ class _TempFile(object):
     if file_path:
       cleanup_path = os.path.join(base_path, _get_first_part(file_path))
       path = os.path.join(base_path, file_path)
-      _makedirs_exist_ok(os.path.dirname(path))
+      os.makedirs(os.path.dirname(path), exist_ok=True)
       # The file may already exist, in which case, ensure it's writable so that
       # it can be truncated.
       if os.path.exists(path) and not os.access(path, os.W_OK):
         stat_info = os.stat(path)
         os.chmod(path, stat_info.st_mode | stat.S_IWUSR)
     else:
-      _makedirs_exist_ok(base_path)
+      os.makedirs(base_path, exist_ok=True)
       fd, path = tempfile.mkstemp(dir=str(base_path))
       os.close(fd)
       cleanup_path = path
@@ -433,7 +417,7 @@ class _TempFile(object):
     tf = cls(path)
 
     if content:
-      if isinstance(content, six.text_type):
+      if isinstance(content, str):
         tf.write_text(content, mode=mode, encoding=encoding, errors=errors)
       else:
         tf.write_bytes(content, mode)
@@ -482,8 +466,6 @@ class _TempFile(object):
       encoding: The encoding to use when writing the text to the file.
       errors: The error handling strategy to use when converting text to bytes.
     """
-    if six.PY2 and isinstance(text, bytes):
-      text = text.decode(encoding, errors)
     with self.open_text(mode, encoding=encoding, errors=errors) as fp:
       fp.write(text)
 
@@ -673,12 +655,12 @@ class TestCase(unittest.TestCase):
       path = os.path.join(test_path, name)
       cleanup_path = os.path.join(test_path, _get_first_part(name))
     else:
-      _makedirs_exist_ok(test_path)
+      os.makedirs(test_path, exist_ok=True)
       path = tempfile.mkdtemp(dir=test_path)
       cleanup_path = path
 
     _rmtree_ignore_errors(cleanup_path)
-    _makedirs_exist_ok(path)
+    os.makedirs(path, exist_ok=True)
 
     self._maybe_add_temp_path_cleanup(cleanup_path, cleanup)
 
@@ -783,7 +765,8 @@ class TestCase(unittest.TestCase):
   @classmethod
   def _get_tempdir_path_cls(cls):
     # type: () -> Text
-    return os.path.join(TEST_TMPDIR.value, _get_qualname(cls))
+    return os.path.join(TEST_TMPDIR.value,
+                        cls.__qualname__.replace('__main__.', ''))
 
   def _get_tempdir_path_test(self):
     # type: () -> Text
@@ -1053,51 +1036,14 @@ class TestCase(unittest.TestCase):
   def assertItemsEqual(self, expected_seq, actual_seq, msg=None):
     """Deprecated, please use assertCountEqual instead.
 
-    This is equivalent to assertCountEqual in Python 3. An implementation of
-    assertCountEqual is also provided by absltest.TestCase for Python 2.
+    This is equivalent to assertCountEqual.
 
     Args:
       expected_seq: A sequence containing elements we are expecting.
       actual_seq: The sequence that we are testing.
       msg: The message to be printed if the test fails.
     """
-    if six.PY3:
-      # The assertItemsEqual method was renamed assertCountEqual in Python 3.2
-      super(TestCase, self).assertCountEqual(expected_seq, actual_seq, msg)
-    else:
-      super(TestCase, self).assertItemsEqual(expected_seq, actual_seq, msg)
-
-  # Only override assertCountEqual in Python 2 to avoid unnecessary calls.
-  if six.PY2:
-
-    def assertCountEqual(self, expected_seq, actual_seq, msg=None):
-      """Tests two sequences have the same elements regardless of order.
-
-      It tests that the first sequence contains the same elements as the
-      second, regardless of their order. When they don't, an error message
-      listing the differences between the sequences will be generated.
-
-      Duplicate elements are not ignored when comparing first and second.
-      It verifies whether each element has the same count in both sequences.
-      Equivalent to:
-
-          self.assertEqual(Counter(list(expected_seq)),
-                           Counter(list(actual_seq)))
-
-      but works with sequences of unhashable objects as well.
-
-      Example:
-          - [0, 1, 1] and [1, 0, 1] compare equal.
-          - [0, 0, 1] and [0, 1] compare unequal.
-
-      Args:
-        expected_seq: A sequence containing elements we are expecting.
-        actual_seq: The sequence that we are testing.
-        msg: The message to be printed if the test fails.
-
-      """
-      # Only call super's method to avoid potential infinite recursions.
-      super(TestCase, self).assertItemsEqual(expected_seq, actual_seq, msg)
+    super().assertCountEqual(expected_seq, actual_seq, msg)
 
   def assertSameElements(self, expected_seq, actual_seq, msg=None):
     """Asserts that two sequences have the same elements (in any order).
@@ -1157,10 +1103,10 @@ class TestCase(unittest.TestCase):
   # has a different error format. However, I find this slightly more readable.
   def assertMultiLineEqual(self, first, second, msg=None, **kwargs):
     """Asserts that two multi-line strings are equal."""
-    assert isinstance(first, six.string_types), (
-        'First argument is not a string: %r' % (first,))
-    assert isinstance(second, six.string_types), (
-        'Second argument is not a string: %r' % (second,))
+    assert isinstance(first,
+                      str), ('First argument is not a string: %r' % (first,))
+    assert isinstance(second,
+                      str), ('Second argument is not a string: %r' % (second,))
     line_limit = kwargs.pop('line_limit', 0)
     if kwargs:
       raise TypeError('Unexpected keyword args {}'.format(tuple(kwargs)))
@@ -1237,14 +1183,14 @@ class TestCase(unittest.TestCase):
       if type(regex) is not regex_type:  # pylint: disable=unidiomatic-typecheck
         self.fail('regexes list must all be the same type.', message)
 
-    if regex_type is bytes and isinstance(actual_str, six.text_type):
+    if regex_type is bytes and isinstance(actual_str, str):
       regexes = [regex.decode('utf-8') for regex in regexes]
-      regex_type = six.text_type
-    elif regex_type is six.text_type and isinstance(actual_str, bytes):
+      regex_type = str
+    elif regex_type is str and isinstance(actual_str, bytes):
       regexes = [regex.encode('utf-8') for regex in regexes]
       regex_type = bytes
 
-    if regex_type is six.text_type:
+    if regex_type is str:
       regex = u'(?:%s)' % u')|(?:'.join(regexes)
     elif regex_type is bytes:
       regex = b'(?:' + (b')|(?:'.join(regexes)) + b')'
@@ -1276,7 +1222,7 @@ class TestCase(unittest.TestCase):
     # We need bytes regexes here because `err` is bytes.
     # Accommodate code which listed their output regexes w/o the b'' prefix by
     # converting them to bytes for the user.
-    if isinstance(regexes[0], six.text_type):
+    if isinstance(regexes[0], str):
       regexes = [regex.encode('utf-8') for regex in regexes]
 
     command_string = get_command_string(command)
@@ -1322,7 +1268,7 @@ class TestCase(unittest.TestCase):
     # We need bytes regexes here because `err` is bytes.
     # Accommodate code which listed their output regexes w/o the b'' prefix by
     # converting them to bytes for the user.
-    if isinstance(regexes[0], six.text_type):
+    if isinstance(regexes[0], str):
       regexes = [regex.encode('utf-8') for regex in regexes]
 
     command_string = get_command_string(command)
@@ -1364,6 +1310,21 @@ class TestCase(unittest.TestCase):
       self.test_func(exc_value)
       return True
 
+  @typing.overload
+  def assertRaisesWithPredicateMatch(
+      self, expected_exception, predicate) -> _AssertRaisesContext:
+    # The purpose of this return statement is to work around
+    # https://github.com/PyCQA/pylint/issues/5273; it is otherwise ignored.
+    return self._AssertRaisesContext(None, None, None)
+
+  @typing.overload
+  def assertRaisesWithPredicateMatch(
+      self, expected_exception, predicate, callable_obj: Callable[..., Any],
+      *args, **kwargs) -> None:
+    # The purpose of this return statement is to work around
+    # https://github.com/PyCQA/pylint/issues/5273; it is otherwise ignored.
+    return self._AssertRaisesContext(None, None, None)
+
   def assertRaisesWithPredicateMatch(self, expected_exception, predicate,
                                      callable_obj=None, *args, **kwargs):
     """Asserts that exception is thrown and predicate(exception) is true.
@@ -1392,6 +1353,22 @@ class TestCase(unittest.TestCase):
     with context:
       callable_obj(*args, **kwargs)
 
+  @typing.overload
+  def assertRaisesWithLiteralMatch(
+      self, expected_exception, expected_exception_message
+  ) -> _AssertRaisesContext:
+    # The purpose of this return statement is to work around
+    # https://github.com/PyCQA/pylint/issues/5273; it is otherwise ignored.
+    return self._AssertRaisesContext(None, None, None)
+
+  @typing.overload
+  def assertRaisesWithLiteralMatch(
+      self, expected_exception, expected_exception_message,
+      callable_obj: Callable[..., Any], *args, **kwargs) -> None:
+    # The purpose of this return statement is to work around
+    # https://github.com/PyCQA/pylint/issues/5273; it is otherwise ignored.
+    return self._AssertRaisesContext(None, None, None)
+
   def assertRaisesWithLiteralMatch(self, expected_exception,
                                    expected_exception_message,
                                    callable_obj=None, *args, **kwargs):
@@ -1502,7 +1479,7 @@ class TestCase(unittest.TestCase):
     subsequence = list(subsequence)
     longest_match = 0
 
-    for start in xrange(1 + len(container) - len(subsequence)):
+    for start in range(1 + len(container) - len(subsequence)):
       if longest_match == len(subsequence):
         break
       index = 0
@@ -1666,8 +1643,8 @@ class TestCase(unittest.TestCase):
 
     if a == b:
       return
-    a_items = Sorted(list(six.iteritems(a)))
-    b_items = Sorted(list(six.iteritems(b)))
+    a_items = Sorted(list(a.items()))
+    b_items = Sorted(list(b.items()))
 
     unexpected = []
     missing = []
@@ -1679,8 +1656,7 @@ class TestCase(unittest.TestCase):
       """Deterministic repr for dict."""
       # Sort the entries based on their repr, not based on their sort order,
       # which will be non-deterministic across executions, for many types.
-      entries = sorted((safe_repr(k), safe_repr(v))
-                       for k, v in six.iteritems(dikt))
+      entries = sorted((safe_repr(k), safe_repr(v)) for k, v in dikt.items())
       return '{%s}' % (', '.join('%s: %s' % pair for pair in entries))
 
     message = ['%s != %s%s' % (Repr(a), Repr(b), ' (%s)' % msg if msg else '')]
@@ -1718,8 +1694,8 @@ class TestCase(unittest.TestCase):
 
   def assertUrlEqual(self, a, b, msg=None):
     """Asserts that urls are equal, ignoring ordering of query params."""
-    parsed_a = urllib.parse.urlparse(a)
-    parsed_b = urllib.parse.urlparse(b)
+    parsed_a = parse.urlparse(a)
+    parsed_b = parse.urlparse(b)
     self.assertEqual(parsed_a.scheme, parsed_b.scheme, msg)
     self.assertEqual(parsed_a.netloc, parsed_b.netloc, msg)
     self.assertEqual(parsed_a.path, parsed_b.path, msg)
@@ -1727,8 +1703,8 @@ class TestCase(unittest.TestCase):
     self.assertEqual(sorted(parsed_a.params.split(';')),
                      sorted(parsed_b.params.split(';')), msg)
     self.assertDictEqual(
-        urllib.parse.parse_qs(parsed_a.query, keep_blank_values=True),
-        urllib.parse.parse_qs(parsed_b.query, keep_blank_values=True), msg)
+        parse.parse_qs(parsed_a.query, keep_blank_values=True),
+        parse.parse_qs(parsed_b.query, keep_blank_values=True), msg)
 
   def assertSameStructure(self, a, b, aname='a', bname='b', msg=None):
     """Asserts that two values contain the same structural content.
@@ -1866,7 +1842,7 @@ def _sorted_list_difference(expected, actual):
 
 def _are_both_of_integer_type(a, b):
   # type: (object, object) -> bool
-  return isinstance(a, six.integer_types) and isinstance(b, six.integer_types)
+  return isinstance(a, int) and isinstance(b, int)
 
 
 def _are_both_of_sequence_type(a, b):
@@ -1930,14 +1906,14 @@ def _walk_structure_for_problems(a, b, aname, bname, problem_list):
   elif (isinstance(a, abc.Sequence) and
         not isinstance(a, _TEXT_OR_BINARY_TYPES)):
     minlen = min(len(a), len(b))
-    for i in xrange(minlen):
+    for i in range(minlen):
       _walk_structure_for_problems(
           a[i], b[i], '%s[%d]' % (aname, i), '%s[%d]' % (bname, i),
           problem_list)
-    for i in xrange(minlen, len(a)):
+    for i in range(minlen, len(a)):
       problem_list.append('%s has [%i] with value %r but %s does not' %
                           (aname, i, a[i], bname))
-    for i in xrange(minlen, len(b)):
+    for i in range(minlen, len(b)):
       problem_list.append('%s lacks [%i] but %s has it with value %r' %
                           (aname, i, bname, b[i]))
 
@@ -1954,7 +1930,7 @@ def get_command_string(command):
   Returns:
     A string suitable for use as a shell command.
   """
-  if isinstance(command, six.string_types):
+  if isinstance(command, str):
     return command
   else:
     if os.name == 'nt':
@@ -1989,7 +1965,7 @@ def get_command_stderr(command, env=None, close_fds=True):
     # standard handles.
     close_fds = False
 
-  use_shell = isinstance(command, six.string_types)
+  use_shell = isinstance(command, str)
   process = subprocess.Popen(
       command,
       close_fds=close_fds,
@@ -2054,7 +2030,7 @@ def _is_in_app_main():
   """Returns True iff app.run is active."""
   f = sys._getframe().f_back  # pylint: disable=protected-access
   while f:
-    if f.f_code == six.get_function_code(app.run):  # pytype: disable=wrong-arg-types
+    if f.f_code == app.run.__code__:
       return True
     f = f.f_back
   return False
@@ -2150,7 +2126,7 @@ def _run_in_app(function, args, kwargs):
     # after the command-line has been parsed. So we have the for loop below
     # to change back flags to their old values.
     argv = FLAGS(sys.argv)
-    for saved_flag in six.itervalues(saved_flags):
+    for saved_flag in saved_flags.values():
       saved_flag.restore_flag()
 
     function(argv, args, kwargs)
@@ -2172,15 +2148,10 @@ def _is_suspicious_attribute(testCaseClass, name):
   if name.startswith('Test') and len(name) > 4 and name[4].isupper():
     attr = getattr(testCaseClass, name)
     if inspect.isfunction(attr) or inspect.ismethod(attr):
-      if six.PY2:
-        args = inspect.getargspec(attr)
-        return (len(args.args) == 1 and args.args[0] == 'self'
-                and args.varargs is None and args.keywords is None)
-      else:
-        args = inspect.getfullargspec(attr)
-        return (len(args.args) == 1 and args.args[0] == 'self'
-                and args.varargs is None and args.varkw is None and
-                not args.kwonlyargs)
+      args = inspect.getfullargspec(attr)
+      return (len(args.args) == 1 and args.args[0] == 'self' and
+              args.varargs is None and args.varkw is None and
+              not args.kwonlyargs)
   return False
 
 
@@ -2418,7 +2389,7 @@ def _setup_sharding(custom_loader=None):
   # the test case names for this shard.
   delegate_get_names = base_loader.getTestCaseNames
 
-  bucket_iterator = itertools.cycle(xrange(total_shards))
+  bucket_iterator = itertools.cycle(range(total_shards))
 
   def getShardedTestCaseNames(testCaseClass):
     filtered_names = []
@@ -2491,7 +2462,7 @@ def _run_and_get_tests_result(argv, args, kwargs, xml_test_runner_class):
     # Use an in-memory buffer (not backed by the actual file) to store the XML
     # report, because some tools modify the file (e.g., create a placeholder
     # with partial information, in case the test process crashes).
-    xml_buffer = six.StringIO()
+    xml_buffer = io.StringIO()
     kwargs['testRunner'].set_default_xml_stream(xml_buffer)  # pytype: disable=attribute-error
 
     # If we've used a seed to randomize test case ordering, we want to record it
@@ -2566,15 +2537,6 @@ def run_tests(argv, args, kwargs):  # pylint: disable=line-too-long
   sys.exit(not result.wasSuccessful())
 
 
-def _get_qualname(cls):
-  # type: (Type) -> Text
-  if six.PY3:
-    name = cls.__qualname__
-  else:
-    name = '{}.{}'.format(cls.__module__, cls.__name__)
-  return name.replace('__main__.', '')
-
-
 def _rmtree_ignore_errors(path):
   # type: (Text) -> None
   if os.path.isfile(path):
@@ -2586,19 +2548,6 @@ def _rmtree_ignore_errors(path):
     shutil.rmtree(path, ignore_errors=True)
 
 
-def _makedirs_exist_ok(dir_name):
-  # type: (Text) -> None
-  if six.PY3:
-    os.makedirs(dir_name, exist_ok=True)  # pylint: disable=unexpected-keyword-arg
-  else:
-    # Python 2 doesn't have the exist_ok arg, so we roll it ourselves
-    try:
-      os.makedirs(dir_name)
-    except OSError as e:
-      if e.errno != errno.EEXIST:
-        raise
-
-
 def _get_first_part(path):
   # type: (Text) -> Text
   parts = path.split(os.sep, 1)
diff --git a/absl/testing/parameterized.py b/absl/testing/parameterized.py
index 4d02c4e..f318b98 100644
--- a/absl/testing/parameterized.py
+++ b/absl/testing/parameterized.py
@@ -217,7 +217,6 @@ import unittest
 
 from absl._collections_abc import abc
 from absl.testing import absltest
-import six
 
 
 _ADDR_RE = re.compile(r'\<([a-zA-Z0-9_\-\.]+) object at 0x[a-fA-F0-9]+\>')
@@ -247,15 +246,14 @@ def _clean_repr(obj):
 
 
 def _non_string_or_bytes_iterable(obj):
-  return (isinstance(obj, abc.Iterable) and
-          not isinstance(obj, six.text_type) and
-          not isinstance(obj, six.binary_type))
+  return (isinstance(obj, abc.Iterable) and not isinstance(obj, str) and
+          not isinstance(obj, bytes))
 
 
 def _format_parameter_list(testcase_params):
   if isinstance(testcase_params, abc.Mapping):
     return ', '.join('%s=%s' % (argname, _clean_repr(value))
-                     for argname, value in six.iteritems(testcase_params))
+                     for argname, value in testcase_params.items())
   elif _non_string_or_bytes_iterable(testcase_params):
     return ', '.join(map(_clean_repr, testcase_params))
   else:
@@ -333,10 +331,11 @@ class _ParameterizedTestIter(object):
                 'Dict for named tests must contain key "%s"' % _NAMED_DICT_KEY)
           # Create a new dict to avoid modifying the supplied testcase_params.
           testcase_name = testcase_params[_NAMED_DICT_KEY]
-          testcase_params = {k: v for k, v in six.iteritems(testcase_params)
-                             if k != _NAMED_DICT_KEY}
+          testcase_params = {
+              k: v for k, v in testcase_params.items() if k != _NAMED_DICT_KEY
+          }
         elif _non_string_or_bytes_iterable(testcase_params):
-          if not isinstance(testcase_params[0], six.string_types):
+          if not isinstance(testcase_params[0], str):
             raise RuntimeError(
                 'The first element of named test parameters is the test name '
                 'suffix and must be a string')
@@ -388,7 +387,7 @@ def _modify_class(class_object, testcases, naming_type):
   # NOTE: _test_params_repr is private to parameterized.TestCase and it's
   # metaclass; do not use it outside of those classes.
   class_object._test_params_reprs = test_params_reprs = {}
-  for name, obj in six.iteritems(class_object.__dict__.copy()):
+  for name, obj in class_object.__dict__.copy().items():
     if (name.startswith(unittest.TestLoader.testMethodPrefix)
         and isinstance(obj, types.FunctionType)):
       delattr(class_object, name)
@@ -396,7 +395,7 @@ def _modify_class(class_object, testcases, naming_type):
       _update_class_dict_for_param_test_case(
           class_object.__name__, methods, test_params_reprs, name,
           _ParameterizedTestIter(obj, testcases, naming_type, name))
-      for meth_name, meth in six.iteritems(methods):
+      for meth_name, meth in methods.items():
         setattr(class_object, meth_name, meth)
 
 
@@ -554,7 +553,7 @@ class TestGeneratorMetaclass(type):
     # NOTE: _test_params_repr is private to parameterized.TestCase and it's
     # metaclass; do not use it outside of those classes.
     test_params_reprs = dct.setdefault('_test_params_reprs', {})
-    for name, obj in six.iteritems(dct.copy()):
+    for name, obj in dct.copy().items():
       if (name.startswith(unittest.TestLoader.testMethodPrefix) and
           _non_string_or_bytes_iterable(obj)):
         # NOTE: `obj` might not be a _ParameterizedTestIter in two cases:
@@ -637,8 +636,7 @@ def _update_class_dict_for_param_test_case(
     test_params_reprs[new_name] = getattr(func, '__x_params_repr__', '')
 
 
-@six.add_metaclass(TestGeneratorMetaclass)
-class TestCase(absltest.TestCase):
+class TestCase(absltest.TestCase, metaclass=TestGeneratorMetaclass):
   """Base class for test cases using the parameters decorator."""
 
   # visibility: private; do not call outside this class.
diff --git a/absl/testing/xml_reporter.py b/absl/testing/xml_reporter.py
index 103827b..da56e39 100644
--- a/absl/testing/xml_reporter.py
+++ b/absl/testing/xml_reporter.py
@@ -27,7 +27,6 @@ import traceback
 import unittest
 from xml.sax import saxutils
 from absl.testing import _pretty_print_reporter
-import six
 
 
 # See http://www.w3.org/TR/REC-xml/#NT-Char
@@ -74,7 +73,7 @@ def _escape_cdata(s):
   Returns:
     An escaped version of the input string.
   """
-  for char, escaped in six.iteritems(_control_character_conversions):
+  for char, escaped in _control_character_conversions.items():
     s = s.replace(char, escaped)
   return s.replace(']]>', ']] >')
 
@@ -90,13 +89,8 @@ def _iso8601_timestamp(timestamp):
   """
   if timestamp is None or timestamp < 0:
     return None
-  # Use utcfromtimestamp in PY2 because it doesn't have a built-in UTC object
-  if six.PY2:
-    return '%s+00:00' % datetime.datetime.utcfromtimestamp(
-        timestamp).isoformat()
-  else:
-    return datetime.datetime.fromtimestamp(
-        timestamp, tz=datetime.timezone.utc).isoformat()
+  return datetime.datetime.fromtimestamp(
+      timestamp, tz=datetime.timezone.utc).isoformat()
 
 
 def _print_xml_element_header(element, attributes, stream, indentation=''):
@@ -110,8 +104,8 @@ def _print_xml_element_header(element, attributes, stream, indentation=''):
   """
   stream.write('%s<%s' % (indentation, element))
   for attribute in attributes:
-    if len(attribute) == 2 \
-        and attribute[0] is not None and attribute[1] is not None:
+    if (len(attribute) == 2 and attribute[0] is not None and
+        attribute[1] is not None):
       stream.write(' %s="%s"' % (attribute[0], attribute[1]))
   stream.write('>\n')
 
@@ -279,7 +273,7 @@ class _TestSuiteResult(object):
     _print_xml_element_header('testsuites', overall_attributes, stream)
     if self._testsuites_properties:
       stream.write('    <properties>\n')
-      for name, value in sorted(six.iteritems(self._testsuites_properties)):
+      for name, value in sorted(self._testsuites_properties.items()):
         stream.write('      <property name="%s" value="%s"></property>\n' %
                      (_escape_xml_attr(name), _escape_xml_attr(str(value))))
       stream.write('    </properties>\n')
diff --git a/absl/tests/command_name_test.py b/absl/tests/command_name_test.py
index 61af1bb..2679521 100644
--- a/absl/tests/command_name_test.py
+++ b/absl/tests/command_name_test.py
@@ -15,18 +15,14 @@
 
 """Tests for absl.command_name."""
 
-from __future__ import absolute_import
-from __future__ import division
-from __future__ import print_function
-
 import ctypes
 import errno
 import os
 import unittest
+from unittest import mock
 
 from absl import command_name
 from absl.testing import absltest
-import mock
 
 
 def _get_kernel_process_name():
diff --git a/third_party/mock.BUILD b/third_party/mock.BUILD
deleted file mode 100644
index 534ff65..0000000
--- a/third_party/mock.BUILD
+++ /dev/null
@@ -1,13 +0,0 @@
-# Description:
-#   mock is a library for testing in Python.
-
-licenses(["notice"])  # BSD
-
-exports_files(["LICENSE.txt"])
-
-py_library(
-    name = "mock",
-    srcs = ["mock.py"],
-    srcs_version = "PY2AND3",
-    visibility = ["//visibility:public"],
-)