diff --git a/lower-constraints.txt b/lower-constraints.txt
index 28180d6c..36314590 100644
--- a/lower-constraints.txt
+++ b/lower-constraints.txt
@@ -28,7 +28,6 @@ keystoneauth1==3.4.0
 linecache2==1.0.0
 MarkupSafe==1.0
 mccabe==0.2.1
-mock==2.0.0
 monotonic==0.6
 mox3==0.20.0
 msgpack-python==0.4.0
diff --git a/troveclient/tests/test_backups.py b/troveclient/tests/test_backups.py
index ba0ed84b..521617d2 100644
--- a/troveclient/tests/test_backups.py
+++ b/troveclient/tests/test_backups.py
@@ -13,11 +13,12 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
-from mock import patch
-import testtools
 from unittest import mock
+from unittest.mock import patch
 import uuid
 
+import testtools
+
 from troveclient.v1 import backups
 
 """