diff --git a/keystone/assignment/backends/sql.py b/keystone/assignment/backends/sql.py
index b0de38d2f1..65e7336323 100644
--- a/keystone/assignment/backends/sql.py
+++ b/keystone/assignment/backends/sql.py
@@ -29,7 +29,7 @@ CONF = config.CONF
 LOG = log.getLogger(__name__)
 
 
-class AssignmentType:
+class AssignmentType(object):
     USER_PROJECT = 'UserProject'
     GROUP_PROJECT = 'GroupProject'
     USER_DOMAIN = 'UserDomain'
diff --git a/keystone/controllers.py b/keystone/controllers.py
index 4c8190f637..25f34bfc43 100644
--- a/keystone/controllers.py
+++ b/keystone/controllers.py
@@ -88,7 +88,7 @@ def register_version(version):
     _VERSIONS.append(version)
 
 
-class MimeTypes:
+class MimeTypes(object):
     JSON = 'application/json'
     JSON_HOME = 'application/json-home'
 
diff --git a/keystone/identity/mapping_backends/mapping.py b/keystone/identity/mapping_backends/mapping.py
index ca738188ce..dddf36c116 100644
--- a/keystone/identity/mapping_backends/mapping.py
+++ b/keystone/identity/mapping_backends/mapping.py
@@ -13,6 +13,6 @@
 # under the License.
 
 
-class EntityType:
+class EntityType(object):
     USER = 'user'
     GROUP = 'group'
diff --git a/keystone/tests/core.py b/keystone/tests/core.py
index 5b3c763b15..b35493ab56 100644
--- a/keystone/tests/core.py
+++ b/keystone/tests/core.py
@@ -92,7 +92,7 @@ os.makedirs(TMPDIR)
 atexit.register(shutil.rmtree, TMPDIR)
 
 
-class dirs:
+class dirs(object):
     @staticmethod
     def root(*p):
         return os.path.join(ROOTDIR, *p)
diff --git a/keystone/tests/test_v3.py b/keystone/tests/test_v3.py
index 28595c59ad..e460c67f29 100644
--- a/keystone/tests/test_v3.py
+++ b/keystone/tests/test_v3.py
@@ -1215,7 +1215,7 @@ class VersionTestCase(RestfulTestCase):
 class AuthContextMiddlewareTestCase(RestfulTestCase):
     def _mock_request_object(self, token_id):
 
-        class fake_req:
+        class fake_req(object):
             headers = {middleware.AUTH_TOKEN_HEADER: token_id}
             environ = {}
 
diff --git a/keystone/tests/unit/common/test_notifications.py b/keystone/tests/unit/common/test_notifications.py
index ab49b6537e..f219c481bc 100644
--- a/keystone/tests/unit/common/test_notifications.py
+++ b/keystone/tests/unit/common/test_notifications.py
@@ -509,7 +509,7 @@ class TestEventCallbacks(test_v3.RestfulTestCase):
         callback_called = []
 
         @dependency.provider('foo_api')
-        class Foo:
+        class Foo(object):
             def __init__(self):
                 self.event_callbacks = {
                     CREATED_OPERATION: {'project': [self.foo_callback]}}
@@ -526,7 +526,7 @@ class TestEventCallbacks(test_v3.RestfulTestCase):
 
     def test_invalid_event_callbacks(self):
         @dependency.provider('foo_api')
-        class Foo:
+        class Foo(object):
             def __init__(self):
                 self.event_callbacks = 'bogus'
 
@@ -534,7 +534,7 @@ class TestEventCallbacks(test_v3.RestfulTestCase):
 
     def test_invalid_event_callbacks_event(self):
         @dependency.provider('foo_api')
-        class Foo:
+        class Foo(object):
             def __init__(self):
                 self.event_callbacks = {CREATED_OPERATION: 'bogus'}
 
diff --git a/tox.ini b/tox.ini
index 5d689f211d..ccffa4e605 100644
--- a/tox.ini
+++ b/tox.ini
@@ -96,8 +96,7 @@ filename= *.py,keystone-all,keystone-manage
 show-source = true
 
 # H405  multi line docstring summary not separated with an empty line
-# New from hacking 0.10: H238
-ignore = H238,H405
+ignore = H405
 
 exclude=.venv,.git,.tox,build,dist,doc,*openstack/common*,*lib/python*,*egg,tools,vendor,.update-venv,*.ini,*.po,*.pot
 max-complexity=24