Merge "Remove all usage of six library"

18 files changed, 124 insertions, 265 deletions

diff --git a/lower-constraints.txt b/lower-constraints.txt
index d95af17..ced789b 100644
--- a/lower-constraints.txt
+++ b/lower-constraints.txt
@@ -29,7 +29,6 @@ PyYAML==3.13
 requests==2.14.2
 requestsexceptions==1.2.0
 rfc3986==0.3.1
-six==1.10.0
 smmap==0.9.0
 stestr==2.0.0
 stevedore==1.20.0
diff --git a/oslo_utils/dictutils.py b/oslo_utils/dictutils.py
index 44affb7..9185428 100644
--- a/oslo_utils/dictutils.py
+++ b/oslo_utils/dictutils.py
@@ -13,8 +13,6 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
-import six
-
 
 def flatten_dict_to_keypairs(d, separator=':'):
     """Generator that produces sequence of keypairs for nested dictionaries.
@@ -22,7 +20,7 @@ def flatten_dict_to_keypairs(d, separator=':'):
     :param d: dictionaries which may be nested
     :param separator: symbol between names
     """
-    for name, value in sorted(six.iteritems(d)):
+    for name, value in sorted(iter(d.items())):
         if isinstance(value, dict):
             for subname, subvalue in flatten_dict_to_keypairs(value,
                                                               separator):
diff --git a/oslo_utils/encodeutils.py b/oslo_utils/encodeutils.py
index 0e177b2..8f94f89 100644
--- a/oslo_utils/encodeutils.py
+++ b/oslo_utils/encodeutils.py
@@ -15,8 +15,6 @@
 
 import sys
 
-import six
-
 
 # NOTE(blk-u): This provides a symbol that can be overridden just for this
 # module during testing. sys.getfilesystemencoding() is called by coverage so
@@ -35,10 +33,10 @@ def safe_decode(text, incoming=None, errors='strict'):
                 representation of it.
     :raises TypeError: If text is not an instance of str
     """
-    if not isinstance(text, (six.string_types, six.binary_type)):
+    if not isinstance(text, (str, bytes)):
         raise TypeError("%s can't be decoded" % type(text))
 
-    if isinstance(text, six.text_type):
+    if isinstance(text, str):
         return text
 
     if not incoming:
@@ -81,7 +79,7 @@ def safe_encode(text, incoming=None,
     See also to_utf8() function which is simpler and don't depend on
     the locale encoding.
     """
-    if not isinstance(text, (six.string_types, six.binary_type)):
+    if not isinstance(text, (str, bytes)):
         raise TypeError("%s can't be encoded" % type(text))
 
     if not incoming:
@@ -94,7 +92,7 @@ def safe_encode(text, incoming=None,
     if hasattr(encoding, 'lower'):
         encoding = encoding.lower()
 
-    if isinstance(text, six.text_type):
+    if isinstance(text, str):
         return text.encode(encoding, errors)
     elif text and encoding != incoming:
         # Decode text before encoding it with `encoding`
@@ -111,9 +109,9 @@ def to_utf8(text):
 
     .. versionadded:: 3.5
     """
-    if isinstance(text, six.binary_type):
+    if isinstance(text, bytes):
         return text
-    elif isinstance(text, six.text_type):
+    elif isinstance(text, str):
         return text.encode('utf-8')
     else:
         raise TypeError("bytes or Unicode expected, got %s"
@@ -133,24 +131,6 @@ def exception_to_unicode(exc):
     .. versionadded:: 1.6
     """
     msg = None
-    if six.PY2:
-        # First try by calling the unicode type constructor. We should try
-        # unicode() before exc.__unicode__() because subclasses of unicode can
-        # be easily casted to unicode, whereas they have no __unicode__()
-        # method.
-        try:
-            msg = unicode(exc)  # NOQA
-        except UnicodeError:
-            # unicode(exc) fail with UnicodeDecodeError on Python 2 if
-            # exc.__unicode__() or exc.__str__() returns a bytes string not
-            # decodable from the default encoding (ASCII)
-            if hasattr(exc, '__unicode__'):
-                # Call directly the __unicode__() method to avoid
-                # the implicit decoding from the default encoding
-                try:
-                    msg = exc.__unicode__()
-                except UnicodeError:  # nosec
-                    pass
 
     if msg is None:
         # Don't call directly str(exc), because it fails with
@@ -158,7 +138,7 @@ def exception_to_unicode(exc):
         # string not encodable to the default encoding (ASCII)
         msg = exc.__str__()
 
-    if isinstance(msg, six.text_type):
+    if isinstance(msg, str):
         # This should be the default path on Python 3 and an *optional* path
         # on Python 2 (if for some reason the exception message was already
         # in unicode instead of the more typical bytes string); so avoid
diff --git a/oslo_utils/excutils.py b/oslo_utils/excutils.py
index 533c7ee..94a6655 100644
--- a/oslo_utils/excutils.py
+++ b/oslo_utils/excutils.py
@@ -18,14 +18,13 @@ Exception related utilities.
 """
 
 import functools
+import io
 import logging
 import os
 import sys
 import time
 import traceback
 
-import six
-
 
 from oslo_utils import encodeutils
 from oslo_utils import reflection
@@ -70,7 +69,7 @@ class CausedByException(Exception):
         if indent < 0:
             raise ValueError("Provided 'indent' must be greater than"
                              " or equal to zero instead of %s" % indent)
-        buf = six.StringIO()
+        buf = io.StringIO()
         if show_root_class:
             buf.write(reflection.get_class_name(self, fully_qualified=False))
             buf.write(": ")
@@ -140,7 +139,7 @@ def raise_with_cause(exc_cls, message, *args, **kwargs):
             # Leave no references around (especially with regards to
             # tracebacks and any variables that it retains internally).
             del(exc_type, exc, exc_tb)
-    six.raise_from(exc_cls(message, *args, **kwargs), kwargs.get('cause'))
+    raise exc_cls(message, *args, **kwargs) from kwargs.get('cause')
 
 
 class save_and_reraise_exception(object):
@@ -193,7 +192,15 @@ class save_and_reraise_exception(object):
         if self.type_ is None and self.value is None:
             raise RuntimeError("There is no (currently) captured exception"
                                " to force the reraising of")
-        six.reraise(self.type_, self.value, self.tb)
+        try:
+            if self.value is None:
+                self.value = self.type_()
+            if self.value.__traceback__ is not self.tb:
+                raise self.value.with_traceback(self.tb)
+            raise self.value
+        finally:
+            self.value = None
+            self.tb = None
 
     def capture(self, check=True):
         (type_, value, tb) = sys.exc_info()
@@ -240,7 +247,7 @@ def forever_retry_uncaught_exceptions(*args, **kwargs):
         retry_delay = max(0.0, float(kwargs.get('retry_delay', 1.0)))
         same_log_delay = max(0.0, float(kwargs.get('same_log_delay', 60.0)))
 
-        @six.wraps(infunc)
+        @functools.wraps(infunc)
         def wrapper(*args, **kwargs):
             last_exc_message = None
             same_failure_count = 0
@@ -339,7 +346,15 @@ class exception_filter(object):
         try:
             if not self._should_ignore_ex(ex):
                 if exc_val is ex:
-                    six.reraise(exc_type, exc_val, traceback)
+                    try:
+                        if exc_val is None:
+                            exc_val = exc_type()
+                        if exc_val.__traceback__ is not traceback:
+                            raise exc_val.with_traceback(traceback)
+                        raise exc_val
+                    finally:
+                        exc_val = None
+                        traceback = None
                 else:
                     raise ex
         finally:
diff --git a/oslo_utils/netutils.py b/oslo_utils/netutils.py
index af06a43..492c726 100644
--- a/oslo_utils/netutils.py
+++ b/oslo_utils/netutils.py
@@ -21,11 +21,10 @@ import logging
 import os
 import re
 import socket
+from urllib import parse
 
 import netaddr
 import netifaces
-import six
-from six.moves.urllib import parse
 
 from oslo_utils._i18n import _
 
@@ -284,7 +283,7 @@ def is_valid_mac(address):
     .. versionadded:: 3.17
     """
     m = "[0-9a-f]{2}(:[0-9a-f]{2}){5}$"
-    return (isinstance(address, six.string_types) and
+    return (isinstance(address, str) and
             re.match(m, address.lower()))
 
 
diff --git a/oslo_utils/reflection.py b/oslo_utils/reflection.py
index c6b360e..8ef7c8d 100644
--- a/oslo_utils/reflection.py
+++ b/oslo_utils/reflection.py
@@ -22,10 +22,9 @@ Reflection module.
 
 import inspect
 import logging
+import operator
 import types
 
-import six
-
 try:
     _TYPE_TYPE = types.TypeType
 except AttributeError:
@@ -40,16 +39,9 @@ _BUILTIN_MODULES = ('builtins', '__builtin__', '__builtins__', 'exceptions')
 LOG = logging.getLogger(__name__)
 
 
-if six.PY3:
-    Parameter = inspect.Parameter
-    Signature = inspect.Signature
-    get_signature = inspect.signature
-else:
-    # Provide an equivalent but use funcsigs instead...
-    import funcsigs
-    Parameter = funcsigs.Parameter
-    Signature = funcsigs.Signature
-    get_signature = funcsigs.signature
+Parameter = inspect.Parameter
+Signature = inspect.Signature
+get_signature = inspect.signature
 
 
 def get_members(obj, exclude_hidden=True):
@@ -85,7 +77,7 @@ def get_class_name(obj, fully_qualified=True, truncate_builtins=True):
 
     if inspect.ismethod(obj):
         obj = get_method_self(obj)
-    if not isinstance(obj, six.class_types):
+    if not isinstance(obj, type):
         obj = type(obj)
     if truncate_builtins:
         try:
@@ -109,7 +101,7 @@ def get_all_class_names(obj, up_to=object,
     in order of method resolution (mro). If up_to parameter is provided,
     only name of classes that are sublcasses to that class are returned.
     """
-    if not isinstance(obj, six.class_types):
+    if not isinstance(obj, type):
         obj = type(obj)
     for cls in obj.mro():
         if issubclass(cls, up_to):
@@ -126,7 +118,7 @@ def get_callable_name(function):
     method_self = get_method_self(function)
     if method_self is not None:
         # This is a bound method.
-        if isinstance(method_self, six.class_types):
+        if isinstance(method_self, type):
             # This is a bound class method.
             im_class = method_self
         else:
@@ -163,7 +155,7 @@ def get_method_self(method):
     if not inspect.ismethod(method):
         return None
     try:
-        return six.get_method_self(method)
+        return operator.attrgetter("__self__")(method)
     except AttributeError:
         return None
 
@@ -203,8 +195,8 @@ def is_same_callback(callback1, callback2, strict=True):
         # another object if the objects have __eq__ methods that return true
         # (when in fact it is a different bound method). Python u so crazy!
         try:
-            self1 = six.get_method_self(callback1)
-            self2 = six.get_method_self(callback2)
+            self1 = operator.attrgetter("__self__")(callback1)
+            self2 = operator.attrgetter("__self__")(callback2)
             return self1 is self2
         except AttributeError:  # nosec
             pass
@@ -231,8 +223,8 @@ def get_callable_args(function, required_only=False):
     are not included into output.
     """
     sig = get_signature(function)
-    function_args = list(six.iterkeys(sig.parameters))
-    for param_name, p in six.iteritems(sig.parameters):
+    function_args = list(iter(sig.parameters.keys()))
+    for param_name, p in iter(sig.parameters.items()):
         if (p.kind in (Parameter.VAR_POSITIONAL, Parameter.VAR_KEYWORD) or
                 (required_only and p.default is not Parameter.empty)):
             function_args.remove(param_name)
@@ -243,4 +235,4 @@ def accepts_kwargs(function):
     """Returns ``True`` if function accepts kwargs otherwise ``False``."""
     sig = get_signature(function)
     return any(p.kind == Parameter.VAR_KEYWORD
-               for p in six.itervalues(sig.parameters))
+               for p in iter(sig.parameters.values()))
diff --git a/oslo_utils/strutils.py b/oslo_utils/strutils.py
index 6295bde..35b15d3 100644
--- a/oslo_utils/strutils.py
+++ b/oslo_utils/strutils.py
@@ -21,10 +21,9 @@ import collections
 import math
 import re
 import unicodedata
+import urllib
 
 import pyparsing as pp
-import six
-from six.moves import urllib
 
 from oslo_utils._i18n import _
 from oslo_utils import encodeutils
@@ -138,8 +137,8 @@ def bool_from_string(subject, strict=False, default=False):
     """
     if isinstance(subject, bool):
         return subject
-    if not isinstance(subject, six.string_types):
-        subject = six.text_type(subject)
+    if not isinstance(subject, str):
+        subject = str(subject)
 
     lowered = subject.strip().lower()
 
@@ -324,7 +323,7 @@ def mask_password(message, secret="***"):  # nosec
     """
 
     try:
-        message = six.text_type(message)
+        message = str(message)
     except UnicodeDecodeError:  # nosec
         # NOTE(jecarey): Temporary fix to handle cases where message is a
         # byte string. A better solution will be provided in Kilo.
@@ -411,7 +410,7 @@ def mask_dict_password(dictionary, secret="***"):  # nosec
         # NOTE(jlvillal): Check to see if anything in the dictionary 'key'
         # contains any key specified in _SANITIZE_KEYS.
         k_matched = False
-        if isinstance(k, six.string_types):
+        if isinstance(k, str):
             for sani_key in _SANITIZE_KEYS:
                 if sani_key in k.lower():
                     out[k] = secret
@@ -420,7 +419,7 @@ def mask_dict_password(dictionary, secret="***"):  # nosec
         if not k_matched:
             # We did not find a match for the key name in the
             # _SANITIZE_KEYS, so we fall through to here
-            if isinstance(v, six.string_types):
+            if isinstance(v, str):
                 out[k] = mask_password(v, secret=secret)
             else:
                 # Just leave it alone.
@@ -438,7 +437,7 @@ def is_int_like(val):
     .. versionadded:: 1.1
     """
     try:
-        return six.text_type(int(val)) == six.text_type(val)
+        return str(int(val)) == str(val)
     except (TypeError, ValueError):
         return False
 
@@ -457,7 +456,7 @@ def check_string_length(value, name=None, min_length=0, max_length=None):
     if name is None:
         name = value
 
-    if not isinstance(value, six.string_types):
+    if not isinstance(value, str):
         msg = _("%s is not a string or unicode") % name
         raise TypeError(msg)
 
diff --git a/oslo_utils/tests/test_eventletutils.py b/oslo_utils/tests/test_eventletutils.py
index 62b72af..ebbdbb0 100644
--- a/oslo_utils/tests/test_eventletutils.py
+++ b/oslo_utils/tests/test_eventletutils.py
@@ -19,7 +19,6 @@ import warnings
 import eventlet
 from eventlet import greenthread
 from oslotest import base as test_base
-import six
 
 from oslo_utils import eventletutils
 
@@ -44,7 +43,7 @@ class EventletUtilsTest(test_base.BaseTestCase):
         self.assertEqual(1, len(capture))
         w = capture[0]
         self.assertEqual(RuntimeWarning, w.category)
-        self.assertIn('os', six.text_type(w.message))
+        self.assertIn('os', str(w.message))
 
     @mock.patch("oslo_utils.eventletutils._patcher")
     def test_warning_not_patched_none_provided(self, mock_patcher):
@@ -57,7 +56,7 @@ class EventletUtilsTest(test_base.BaseTestCase):
         w = capture[0]
         self.assertEqual(RuntimeWarning, w.category)
         for m in eventletutils._ALL_PATCH:
-            self.assertIn(m, six.text_type(w.message))
+            self.assertIn(m, str(w.message))
 
     @mock.patch("oslo_utils.eventletutils._patcher")
     def test_warning_not_patched_all(self, mock_patcher):
@@ -70,7 +69,7 @@ class EventletUtilsTest(test_base.BaseTestCase):
         w = capture[0]
         self.assertEqual(RuntimeWarning, w.category)
         for m in eventletutils._ALL_PATCH:
-            self.assertIn(m, six.text_type(w.message))
+            self.assertIn(m, str(w.message))
 
     @mock.patch("oslo_utils.eventletutils._patcher")
     def test_no_warning(self, mock_patcher):
@@ -118,7 +117,7 @@ class EventletUtilsTest(test_base.BaseTestCase):
         w = capture[0]
         self.assertEqual(RuntimeWarning, w.category)
         for m in ['os', 'thread']:
-            self.assertNotIn(m, six.text_type(w.message))
+            self.assertNotIn(m, str(w.message))
 
     def test_invalid_patch_check(self):
         self.assertRaises(ValueError,
@@ -133,10 +132,7 @@ class EventletUtilsTest(test_base.BaseTestCase):
         self.assertIsInstance(e_event, eventletutils.EventletEvent)
 
         t_event = eventletutils.Event()
-        if six.PY3:
-            t_event_cls = threading.Event
-        else:
-            t_event_cls = threading._Event
+        t_event_cls = threading.Event
         self.assertIsInstance(t_event, t_event_cls)
 
         public_methods = [m for m in dir(t_event) if not m.startswith("_") and
diff --git a/oslo_utils/tests/test_fileutils.py b/oslo_utils/tests/test_fileutils.py
index f70b2f4..e45d1e9 100644
--- a/oslo_utils/tests/test_fileutils.py
+++ b/oslo_utils/tests/test_fileutils.py
@@ -26,7 +26,6 @@ import uuid
 import yaml
 
 from oslotest import base as test_base
-import six
 
 from oslo_utils import fileutils
 
@@ -131,7 +130,7 @@ class WriteToTempfileTestCase(test_base.BaseTestCase):
     def check_file_content(self, path):
         with open(path, 'r') as fd:
             ans = fd.read()
-            self.assertEqual(self.content, six.b(ans))
+            self.assertEqual(self.content, ans.encode("latin-1"))
 
     def test_file_without_path_and_suffix(self):
         res = fileutils.write_to_tempfile(self.content)
@@ -204,7 +203,7 @@ class TestComputeFileChecksum(test_base.BaseTestCase):
     def check_file_content(self, content, path):
         with open(path, 'r') as fd:
             ans = fd.read()
-            self.assertEqual(content, six.b(ans))
+            self.assertEqual(content, ans.encode("latin-1"))
 
     def test_compute_checksum_default_algorithm(self):
         path = fileutils.write_to_tempfile(self.content)
diff --git a/oslo_utils/tests/test_fixture.py b/oslo_utils/tests/test_fixture.py
index 5775136..b106f15 100644
--- a/oslo_utils/tests/test_fixture.py
+++ b/oslo_utils/tests/test_fixture.py
@@ -17,7 +17,6 @@
 import datetime
 
 from oslotest import base as test_base
-import six
 
 from oslo_utils import fixture
 from oslo_utils.fixture import uuidsentinel as uuids
@@ -81,4 +80,4 @@ class UUIDSentinelsTest(test_base.BaseTestCase):
 
     def test_with_underline_prefix(self):
         ex = self.assertRaises(AttributeError, getattr, uuids, '_foo')
-        self.assertIn("Sentinels must not start with _", six.text_type(ex))
+        self.assertIn("Sentinels must not start with _", str(ex))
diff --git a/oslo_utils/tests/test_fnmatch.py b/oslo_utils/tests/test_fnmatch.py
index 78e11e6..ec9583d 100644
--- a/oslo_utils/tests/test_fnmatch.py
+++ b/oslo_utils/tests/test_fnmatch.py
@@ -13,11 +13,9 @@
 import fnmatch as standard_fnmatch
 import ntpath
 import posixpath
-import sys
 from unittest import mock
 
 from oslotest import base
-import six
 
 
 fnmatch = None
@@ -48,12 +46,3 @@ class TestFnmatch(base.BaseTestCase):
 
         fnmatch = standard_fnmatch
         self._test_fnmatch_posix_nt()
-
-        with mock.patch.object(sys, 'version_info', new=(2, 7, 11)):
-            from oslo_utils import fnmatch as oslo_fnmatch
-            fnmatch = oslo_fnmatch
-            self._test_fnmatch_posix_nt()
-
-        with mock.patch.object(sys, 'version_info', new=(2, 7, 0)):
-            six.moves.reload_module(oslo_fnmatch)
-            self._test_fnmatch_posix_nt()
diff --git a/oslo_utils/tests/test_netutils.py b/oslo_utils/tests/test_netutils.py
index 260e1b1..28bb1d9 100644
--- a/oslo_utils/tests/test_netutils.py
+++ b/oslo_utils/tests/test_netutils.py
@@ -14,13 +14,13 @@
 #    under the License.
 
 import contextlib
+import io
 import socket
 from unittest import mock
 
 import netaddr
 import netifaces
 from oslotest import base as test_base
-import six
 
 from oslo_utils import netutils
 
@@ -393,7 +393,7 @@ class MACbyIPv6TestCase(test_base.BaseTestCase):
 @contextlib.contextmanager
 def mock_file_content(content):
     # Allows StringIO to act like a context manager-enabled file.
-    yield six.StringIO(content)
+    yield io.StringIO(content)
 
 
 class TestIsIPv6Enabled(test_base.BaseTestCase):
@@ -407,19 +407,19 @@ class TestIsIPv6Enabled(test_base.BaseTestCase):
         self.addCleanup(reset_detection_flag)
 
     @mock.patch('os.path.exists', return_value=True)
-    @mock.patch('six.moves.builtins.open', return_value=mock_file_content('0'))
+    @mock.patch('builtins.open', return_value=mock_file_content('0'))
     def test_enabled(self, mock_open, exists):
         enabled = netutils.is_ipv6_enabled()
         self.assertTrue(enabled)
 
     @mock.patch('os.path.exists', return_value=True)
-    @mock.patch('six.moves.builtins.open', return_value=mock_file_content('1'))
+    @mock.patch('builtins.open', return_value=mock_file_content('1'))
     def test_disabled(self, mock_open, exists):
         enabled = netutils.is_ipv6_enabled()
         self.assertFalse(enabled)
 
     @mock.patch('os.path.exists', return_value=False)
-    @mock.patch('six.moves.builtins.open',
+    @mock.patch('builtins.open',
                 side_effect=AssertionError('should not read'))
     def test_disabled_non_exists(self, mock_open, exists):
         enabled = netutils.is_ipv6_enabled()
@@ -429,14 +429,14 @@ class TestIsIPv6Enabled(test_base.BaseTestCase):
     def test_memoize_enabled(self, exists):
         # Reset the flag to appear that we haven't looked for it yet.
         netutils._IS_IPV6_ENABLED = None
-        with mock.patch('six.moves.builtins.open',
+        with mock.patch('builtins.open',
                         return_value=mock_file_content('0')) as mock_open:
             enabled = netutils.is_ipv6_enabled()
             self.assertTrue(mock_open.called)
             self.assertTrue(netutils._IS_IPV6_ENABLED)
             self.assertTrue(enabled)
         # The second call should not use open again
-        with mock.patch('six.moves.builtins.open',
+        with mock.patch('builtins.open',
                         side_effect=AssertionError('should not be called')):
             enabled = netutils.is_ipv6_enabled()
             self.assertTrue(enabled)
@@ -445,18 +445,18 @@ class TestIsIPv6Enabled(test_base.BaseTestCase):
     def test_memoize_disabled(self, exists):
         # Reset the flag to appear that we haven't looked for it yet.
         netutils._IS_IPV6_ENABLED = None
-        with mock.patch('six.moves.builtins.open',
+        with mock.patch('builtins.open',
                         return_value=mock_file_content('1')):
             enabled = netutils.is_ipv6_enabled()
             self.assertFalse(enabled)
         # The second call should not use open again
-        with mock.patch('six.moves.builtins.open',
+        with mock.patch('builtins.open',
                         side_effect=AssertionError('should not be called')):
             enabled = netutils.is_ipv6_enabled()
             self.assertFalse(enabled)
 
     @mock.patch('os.path.exists', return_value=False)
-    @mock.patch('six.moves.builtins.open',
+    @mock.patch('builtins.open',
                 side_effect=AssertionError('should not read'))
     def test_memoize_not_exists(self, mock_open, exists):
         # Reset the flag to appear that we haven't looked for it yet.
diff --git a/oslo_utils/tests/test_reflection.py b/oslo_utils/tests/test_reflection.py
index 8ca49e9..f104a87 100644
--- a/oslo_utils/tests/test_reflection.py
+++ b/oslo_utils/tests/test_reflection.py
@@ -14,26 +14,21 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
+import functools
 import sys
 
 from oslotest import base as test_base
-import six
-import testtools
 
 from oslo_utils import reflection
 
 
-if six.PY3:
-    RUNTIME_ERROR_CLASSES = ['RuntimeError', 'Exception',
-                             'BaseException', 'object']
-else:
-    RUNTIME_ERROR_CLASSES = ['RuntimeError', 'StandardError', 'Exception',
-                             'BaseException', 'object']
+RUNTIME_ERROR_CLASSES = ['RuntimeError', 'Exception',
+                         'BaseException', 'object']
 
 
 def dummy_decorator(f):
 
-    @six.wraps(f)
+    @functools.wraps(f)
     def wrapper(*args, **kwargs):
         return f(*args, **kwargs)
 
@@ -192,13 +187,8 @@ class GetCallableNameTest(test_base.BaseTestCase):
 
     def test_static_method(self):
         name = reflection.get_callable_name(Class.static_method)
-        if six.PY3:
-            self.assertEqual('.'.join((__name__, 'Class', 'static_method')),
-                             name)
-        else:
-            # NOTE(imelnikov): static method are just functions, class name
-            # is not recorded anywhere in them.
-            self.assertEqual('.'.join((__name__, 'static_method')), name)
+        self.assertEqual('.'.join((__name__, 'Class', 'static_method')),
+                         name)
 
     def test_class_method(self):
         name = reflection.get_callable_name(Class.class_method)
@@ -218,9 +208,6 @@ class GetCallableNameTest(test_base.BaseTestCase):
                                    '__call__')), name)
 
 
-# These extended/special case tests only work on python 3, due to python 2
-# being broken/incorrect with regard to these special cases...
-@testtools.skipIf(not six.PY3, 'python 3.x is not currently available')
 class GetCallableNameTestExtended(test_base.BaseTestCase):
     # Tests items in http://legacy.python.org/dev/peps/pep-3155/
 
diff --git a/oslo_utils/tests/test_strutils.py b/oslo_utils/tests/test_strutils.py
index f43cef2..0ee35b8 100644
--- a/oslo_utils/tests/test_strutils.py
+++ b/oslo_utils/tests/test_strutils.py
@@ -22,7 +22,6 @@ from unittest import mock
 
 import ddt
 from oslotest import base as test_base
-import six
 import testscenarios
 
 from oslo_utils import strutils
@@ -33,12 +32,6 @@ load_tests = testscenarios.load_tests_apply_scenarios
 
 class StrUtilsTest(test_base.BaseTestCase):
 
-    @mock.patch("six.text_type")
-    def test_bool_bool_from_string_no_text(self, mock_text):
-        self.assertTrue(strutils.bool_from_string(True))
-        self.assertFalse(strutils.bool_from_string(False))
-        self.assertEqual(0, mock_text.call_count)
-
     def test_bool_bool_from_string(self):
         self.assertTrue(strutils.bool_from_string(True))
         self.assertFalse(strutils.bool_from_string(False))
@@ -85,7 +78,7 @@ class StrUtilsTest(test_base.BaseTestCase):
         self._test_bool_from_string(lambda s: s)
 
     def test_unicode_bool_from_string(self):
-        self._test_bool_from_string(six.text_type)
+        self._test_bool_from_string(str)
         self.assertFalse(strutils.bool_from_string(u'使用', strict=False))
 
         exc = self.assertRaises(ValueError, strutils.bool_from_string,
@@ -93,7 +86,7 @@ class StrUtilsTest(test_base.BaseTestCase):
         expected_msg = (u"Unrecognized value '使用', acceptable values are:"
                         u" '0', '1', 'f', 'false', 'n', 'no', 'off', 'on',"
                         u" 't', 'true', 'y', 'yes'")
-        self.assertEqual(expected_msg, six.text_type(exc))
+        self.assertEqual(expected_msg, str(exc))
 
     def test_other_bool_from_string(self):
         self.assertFalse(strutils.bool_from_string(None))
@@ -170,16 +163,17 @@ class StrUtilsTest(test_base.BaseTestCase):
     def test_slugify(self):
         to_slug = strutils.to_slug
         self.assertRaises(TypeError, to_slug, True)
-        self.assertEqual(six.u("hello"), to_slug("hello"))
-        self.assertEqual(six.u("two-words"), to_slug("Two Words"))
-        self.assertEqual(six.u("ma-any-spa-ce-es"),
+        self.assertEqual("hello", to_slug("hello"))
+        self.assertEqual("two-words", to_slug("Two Words"))
+        self.assertEqual("ma-any-spa-ce-es",
                          to_slug("Ma-any\t spa--ce- es"))
-        self.assertEqual(six.u("excamation"), to_slug("exc!amation!"))
-        self.assertEqual(six.u("ampserand"), to_slug("&ampser$and"))
-        self.assertEqual(six.u("ju5tnum8er"), to_slug("ju5tnum8er"))
-        self.assertEqual(six.u("strip-"), to_slug(" strip - "))
-        self.assertEqual(six.u("perche"), to_slug(six.b("perch\xc3\xa9")))
-        self.assertEqual(six.u("strange"),
+        self.assertEqual("excamation", to_slug("exc!amation!"))
+        self.assertEqual("ampserand", to_slug("&ampser$and"))
+        self.assertEqual("ju5tnum8er", to_slug("ju5tnum8er"))
+        self.assertEqual("strip-", to_slug(" strip - "))
+        self.assertEqual("perche",
+                         to_slug("perch\xc3\xa9".encode("latin-1")))
+        self.assertEqual("strange",
                          to_slug("\x80strange", errors="ignore"))
 
 
@@ -619,12 +613,12 @@ class MaskPasswordTestCase(test_base.BaseTestCase):
         self.assertEqual(expected, strutils.mask_password(payload))
 
         payload = """{'adminPass':'TL0EfN33'}"""
-        payload = six.text_type(payload)
+        payload = str(payload)
         expected = """{'adminPass':'***'}"""
         self.assertEqual(expected, strutils.mask_password(payload))
 
         payload = """{'token':'mytoken'}"""
-        payload = six.text_type(payload)
+        payload = str(payload)
         expected = """{'token':'***'}"""
         self.assertEqual(expected, strutils.mask_password(payload))
 
@@ -950,7 +944,7 @@ class ValidateIntegerTestCase(test_base.BaseTestCase):
                "min_value": 300, "max_value": 300},
               {"value": 55, "name": "doing 55 in a 54",
                "max_value": 54},
-              {"value": six.unichr(129), "name": "UnicodeError",
+              {"value": chr(129), "name": "UnicodeError",
                "max_value": 1000})
     def test_invalid_inputs(self, value, name, **kwargs):
         self.assertRaises(ValueError, strutils.validate_integer,
diff --git a/oslo_utils/tests/tests_encodeutils.py b/oslo_utils/tests/tests_encodeutils.py
index 546e8ea..b2f914f 100644
--- a/oslo_utils/tests/tests_encodeutils.py
+++ b/oslo_utils/tests/tests_encodeutils.py
@@ -19,8 +19,6 @@ from unittest import mock
 
 from oslo_i18n import fixture as oslo_i18n_fixture
 from oslotest import base as test_base
-import six
-import testtools
 
 from oslo_utils import encodeutils
 
@@ -30,25 +28,23 @@ class EncodeUtilsTest(test_base.BaseTestCase):
     def test_safe_decode(self):
         safe_decode = encodeutils.safe_decode
         self.assertRaises(TypeError, safe_decode, True)
-        self.assertEqual(six.u('ni\xf1o'), safe_decode(six.b("ni\xc3\xb1o"),
-                         incoming="utf-8"))
-        if six.PY2:
-            # In Python 3, bytes.decode() doesn't support anymore
-            # bytes => bytes encodings like base64
-            self.assertEqual(six.u("test"), safe_decode("dGVzdA==",
-                             incoming='base64'))
-
-        self.assertEqual(six.u("strange"), safe_decode(six.b('\x80strange'),
-                         errors='ignore'))
-
-        self.assertEqual(six.u('\xc0'), safe_decode(six.b('\xc0'),
+        self.assertEqual('ni\xf1o',
+                         safe_decode("ni\xc3\xb1o".encode("latin-1"),
+                                     incoming="utf-8"))
+
+        self.assertEqual("strange",
+                         safe_decode('\x80strange'.encode("latin-1"),
+                                     errors='ignore'))
+
+        self.assertEqual('\xc0', safe_decode('\xc0'.encode("latin-1"),
                          incoming='iso-8859-1'))
 
         # Forcing incoming to ascii so it falls back to utf-8
-        self.assertEqual(six.u('ni\xf1o'), safe_decode(six.b('ni\xc3\xb1o'),
-                         incoming='ascii'))
+        self.assertEqual('ni\xf1o',
+                         safe_decode('ni\xc3\xb1o'.encode("latin-1"),
+                                     incoming='ascii'))
 
-        self.assertEqual(six.u('foo'), safe_decode(b'foo'))
+        self.assertEqual('foo', safe_decode(b'foo'))
 
     def test_safe_encode_none_instead_of_text(self):
         self.assertRaises(TypeError, encodeutils.safe_encode, None)
@@ -68,28 +64,18 @@ class EncodeUtilsTest(test_base.BaseTestCase):
     def test_safe_encode_tuple_instead_of_text(self):
         self.assertRaises(TypeError, encodeutils.safe_encode, ('foo', 'bar', ))
 
-    def test_safe_encode_py2(self):
-        if six.PY2:
-            # In Python 3, str.encode() doesn't support anymore
-            # text => text encodings like base64
-            self.assertEqual(
-                six.b("dGVzdA==\n"),
-                encodeutils.safe_encode("test", encoding='base64'),
-            )
-        else:
-            self.skipTest("Requires py2.x")
-
     def test_safe_encode_force_incoming_utf8_to_ascii(self):
         # Forcing incoming to ascii so it falls back to utf-8
         self.assertEqual(
-            six.b('ni\xc3\xb1o'),
-            encodeutils.safe_encode(six.b('ni\xc3\xb1o'), incoming='ascii'),
+            'ni\xc3\xb1o'.encode("latin-1"),
+            encodeutils.safe_encode('ni\xc3\xb1o'.encode("latin-1"),
+                                    incoming='ascii'),
         )
 
     def test_safe_encode_same_encoding_different_cases(self):
         with mock.patch.object(encodeutils, 'safe_decode', mock.Mock()):
             utf8 = encodeutils.safe_encode(
-                six.u('foo\xf1bar'), encoding='utf-8')
+                'foo\xf1bar', encoding='utf-8')
             self.assertEqual(
                 encodeutils.safe_encode(utf8, 'UTF-8', 'utf-8'),
                 encodeutils.safe_encode(utf8, 'utf-8', 'UTF-8'),
@@ -101,11 +87,11 @@ class EncodeUtilsTest(test_base.BaseTestCase):
             encodeutils.safe_decode.assert_has_calls([])
 
     def test_safe_encode_different_encodings(self):
-        text = six.u('foo\xc3\xb1bar')
+        text = 'foo\xc3\xb1bar'
         result = encodeutils.safe_encode(
             text=text, incoming='utf-8', encoding='iso-8859-1')
         self.assertNotEqual(text, result)
-        self.assertNotEqual(six.b("foo\xf1bar"), result)
+        self.assertNotEqual("foo\xf1bar".encode("latin-1"), result)
 
     def test_to_utf8(self):
         self.assertEqual(encodeutils.to_utf8(b'a\xe9\xff'),        # bytes
@@ -115,7 +101,7 @@ class EncodeUtilsTest(test_base.BaseTestCase):
         self.assertRaises(TypeError, encodeutils.to_utf8, 123)     # invalid
 
         # oslo.i18n Message objects should also be accepted for convenience.
-        # It works because Message is a subclass of six.text_type. Use the
+        # It works because Message is a subclass of str. Use the
         # lazy translation to get a Message instance of oslo_i18n.
         msg = oslo_i18n_fixture.Translation().lazy("test")
         self.assertEqual(encodeutils.to_utf8(msg),
@@ -177,79 +163,6 @@ class ExceptionToUnicodeTest(test_base.BaseTestCase):
             self.assertEqual(encodeutils.exception_to_unicode(exc),
                              u'\u0420\u0443\u0441\u0441\u043a\u0438\u0439')
 
-    @testtools.skipIf(six.PY3, 'test specific to Python 2')
-    def test_unicode_exception(self):
-        # Exception with a __unicode__() method, but no __str__()
-        class UnicodeException(Exception):
-            def __init__(self, value):
-                Exception.__init__(self)
-                self.value = value
-
-            def __unicode__(self):
-                return self.value
-
-        # __unicode__() returns unicode
-        exc = UnicodeException(u'unicode \xe9\u20ac')
-        self.assertEqual(encodeutils.exception_to_unicode(exc),
-                         u'unicode \xe9\u20ac')
-
-        # __unicode__() returns bytes (does this case really happen in the
-        # wild?)
-        exc = UnicodeException(b'utf-8 \xc3\xa9\xe2\x82\xac')
-        self.assertEqual(encodeutils.exception_to_unicode(exc),
-                         u'utf-8 \xe9\u20ac')
-
-    @testtools.skipIf(six.PY3, 'test specific to Python 2')
-    def test_unicode_or_str_exception(self):
-        # Exception with __str__() and __unicode__() methods
-        class UnicodeOrStrException(Exception):
-            def __init__(self, unicode_value, str_value):
-                Exception.__init__(self)
-                self.unicode_value = unicode_value
-                self.str_value = str_value
-
-            def __unicode__(self):
-                return self.unicode_value
-
-            def __str__(self):
-                return self.str_value
-
-        # __unicode__() returns unicode
-        exc = UnicodeOrStrException(u'unicode \xe9\u20ac', b'str')
-        self.assertEqual(encodeutils.exception_to_unicode(exc),
-                         u'unicode \xe9\u20ac')
-
-        # __unicode__() returns bytes (does this case really happen in the
-        # wild?)
-        exc = UnicodeOrStrException(b'utf-8 \xc3\xa9\xe2\x82\xac', b'str')
-        self.assertEqual(encodeutils.exception_to_unicode(exc),
-                         u'utf-8 \xe9\u20ac')
-
-    @testtools.skipIf(six.PY3, 'test specific to Python 2')
-    def test_unicode_only_exception(self):
-        # Exception with a __unicode__() method and a __str__() which
-        # raises an exception (similar to the Message class of oslo_i18n)
-        class UnicodeOnlyException(Exception):
-            def __init__(self, value):
-                Exception.__init__(self)
-                self.value = value
-
-            def __unicode__(self):
-                return self.value
-
-            def __str__(self):
-                raise UnicodeError("use unicode()")
-
-        # __unicode__() returns unicode
-        exc = UnicodeOnlyException(u'unicode \xe9\u20ac')
-        self.assertEqual(encodeutils.exception_to_unicode(exc),
-                         u'unicode \xe9\u20ac')
-
-        # __unicode__() returns bytes
-        exc = UnicodeOnlyException(b'utf-8 \xc3\xa9\xe2\x82\xac')
-        self.assertEqual(encodeutils.exception_to_unicode(exc),
-                         u'utf-8 \xe9\u20ac')
-
     def test_oslo_i18n_message(self):
         # use the lazy translation to get a Message instance of oslo_i18n
         exc = oslo_i18n_fixture.Translation().lazy("test")
diff --git a/oslo_utils/timeutils.py b/oslo_utils/timeutils.py
index 5512918..cb12e0b 100644
--- a/oslo_utils/timeutils.py
+++ b/oslo_utils/timeutils.py
@@ -19,13 +19,13 @@ Time related utilities and helper functions.
 
 import calendar
 import datetime
+import functools
 import logging
 import time
 
 from debtcollector import removals
 import iso8601
 import pytz
-import six
 
 from oslo_utils import reflection
 
@@ -66,9 +66,9 @@ def parse_isotime(timestr):
     try:
         return iso8601.parse_date(timestr)
     except iso8601.ParseError as e:
-        raise ValueError(six.text_type(e))
+        raise ValueError(str(e))
     except TypeError as e:
-        raise ValueError(six.text_type(e))
+        raise ValueError(str(e))
 
 
 @removals.remove(
@@ -114,7 +114,7 @@ def is_older_than(before, seconds):
        Accept datetime string with timezone information.
        Fix comparison with timezone aware datetime.
     """
-    if isinstance(before, six.string_types):
+    if isinstance(before, str):
         before = parse_isotime(before)
 
     before = normalize_time(before)
@@ -129,7 +129,7 @@ def is_newer_than(after, seconds):
        Accept datetime string with timezone information.
        Fix comparison with timezone aware datetime.
     """
-    if isinstance(after, six.string_types):
+    if isinstance(after, str):
         after = parse_isotime(after)
 
     after = normalize_time(after)
@@ -377,7 +377,7 @@ def time_it(logger, log_level=logging.DEBUG,
         if not enabled:
             return func
 
-        @six.wraps(func)
+        @functools.wraps(func)
         def wrapper(*args, **kwargs):
             with StopWatch() as w:
                 result = func(*args, **kwargs)
diff --git a/oslo_utils/versionutils.py b/oslo_utils/versionutils.py
index db8ed0c..9882700 100644
--- a/oslo_utils/versionutils.py
+++ b/oslo_utils/versionutils.py
@@ -19,8 +19,9 @@ Helpers for comparing version strings.
 .. versionadded:: 1.6
 """
 
+import functools
+
 import packaging.version
-import six
 
 from oslo_utils._i18n import _
 
@@ -57,13 +58,13 @@ def convert_version_to_int(version):
     .. versionadded:: 2.0
     """
     try:
-        if isinstance(version, six.string_types):
+        if isinstance(version, str):
             version = convert_version_to_tuple(version)
         if isinstance(version, tuple):
-            return six.moves.reduce(lambda x, y: (x * 1000) + y, version)
+            return functools.reduce(lambda x, y: (x * 1000) + y, version)
     except Exception as ex:
         msg = _("Version %s is invalid.") % version
-        six.raise_from(ValueError(msg), ex)
+        raise ValueError(msg) from ex
 
 
 def convert_version_to_str(version_int):
@@ -75,7 +76,7 @@ def convert_version_to_str(version_int):
     factor = 1000
     while version_int != 0:
         version_number = version_int - (version_int // factor * factor)
-        version_numbers.insert(0, six.text_type(version_number))
+        version_numbers.insert(0, str(version_number))
         version_int = version_int // factor
 
     return '.'.join(map(str, version_numbers))
diff --git a/requirements.txt b/requirements.txt
index 22d2b78..ddc07f0 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -8,7 +8,6 @@
 # that is a likely indicator that the feature belongs somewhere else.
 
 pbr!=2.1.0,>=2.0.0 # Apache-2.0
-six>=1.10.0 # MIT
 iso8601>=0.1.11 # MIT
 oslo.i18n>=3.15.3 # Apache-2.0
 pytz>=2013.6 # MIT