diff --git a/.zuul.yaml b/.zuul.yaml
index 18efca1..fd189e2 100644
--- a/.zuul.yaml
+++ b/.zuul.yaml
@@ -1,4 +1,3 @@
 - project:
     templates:
-      - python35-charm-jobs
-      - openstack-python3-train-jobs
+      - openstack-python3-ussuri-jobs
diff --git a/test-requirements.txt b/test-requirements.txt
index bb1307f..208032f 100644
--- a/test-requirements.txt
+++ b/test-requirements.txt
@@ -28,11 +28,6 @@ oslo.utils<=3.41.0;python_version<'3.6'
 requests>=2.18.4
 charms.reactive
 
-# Newer mock seems to have some syntax which is newer than python3.5 (e.g.
-# f'{something}'
-mock>=1.2,<4.0.0; python_version < '3.6'
-mock>=1.2; python_version >= '3.6'
-
 nose>=1.3.7
 coverage>=3.6
 git+https://github.com/openstack/charms.openstack.git#egg=charms.openstack
diff --git a/unit_tests/__init__.py b/unit_tests/__init__.py
index e201cca..cfad287 100644
--- a/unit_tests/__init__.py
+++ b/unit_tests/__init__.py
@@ -25,7 +25,7 @@ sys.path.append('src/actions')
 import charms_openstack.test_mocks  # noqa
 charms_openstack.test_mocks.mock_charmhelpers()
 
-import mock
+from unittest import mock
 import charms
 keystoneauth1 = mock.MagicMock()
 sys.modules['keystoneauth1'] = keystoneauth1
diff --git a/unit_tests/test_actions.py b/unit_tests/test_actions.py
index a40772d..6522394 100644
--- a/unit_tests/test_actions.py
+++ b/unit_tests/test_actions.py
@@ -12,7 +12,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-import mock
+from unittest import mock
 
 import charms_openstack.test_utils as test_utils
 
diff --git a/unit_tests/test_keystone_saml_mellon_handlers.py b/unit_tests/test_keystone_saml_mellon_handlers.py
index bd4622f..de1bcbd 100644
--- a/unit_tests/test_keystone_saml_mellon_handlers.py
+++ b/unit_tests/test_keystone_saml_mellon_handlers.py
@@ -12,7 +12,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-import mock
+from unittest import mock
 
 import charm.openstack.keystone_saml_mellon as keystone_saml_mellon
 import reactive.keystone_saml_mellon_handlers as handlers
diff --git a/unit_tests/test_lib_charm_openstack_keystone_saml_mellon.py b/unit_tests/test_lib_charm_openstack_keystone_saml_mellon.py
index 9de5a53..a54cced 100644
--- a/unit_tests/test_lib_charm_openstack_keystone_saml_mellon.py
+++ b/unit_tests/test_lib_charm_openstack_keystone_saml_mellon.py
@@ -12,8 +12,8 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-import mock
 import urllib.error
+from unittest import mock
 
 import charms_openstack.test_utils as test_utils