diff --git a/api/controller/artifacts_unittest.py b/api/controller/artifacts_unittest.py
index b7d1b66..eb5e2d9 100644
--- a/api/controller/artifacts_unittest.py
+++ b/api/controller/artifacts_unittest.py
@@ -7,9 +7,10 @@
 
 from __future__ import print_function
 
-import mock
 import os
 
+import mock
+
 from chromite.api import api_config
 from chromite.api.controller import artifacts
 from chromite.api.gen.chromite.api import artifacts_pb2