diff --git a/test/unit/common/middleware/test_memcache.py b/test/unit/common/middleware/test_memcache.py
index ef706ca98e..cbe04d2fe1 100644
--- a/test/unit/common/middleware/test_memcache.py
+++ b/test/unit/common/middleware/test_memcache.py
@@ -297,7 +297,7 @@ class TestCacheMiddleware(unittest.TestCase):
             f.write(dedent(config))
         memcache_ring = self._loadapp(config_path)
         # only one server by default
-        self.assertEqual(memcache_ring._client_cache.keys(),
+        self.assertEqual(list(memcache_ring._client_cache.keys()),
                          ['127.0.0.1:11211'])
         # extra options
         self.assertEqual(memcache_ring._connect_timeout, 0.3)
diff --git a/tox.ini b/tox.ini
index bee7fc3025..a87283b53b 100644
--- a/tox.ini
+++ b/tox.ini
@@ -49,6 +49,7 @@ commands =
       test/unit/common/middleware/test_healthcheck.py \
       test/unit/common/middleware/test_list_endpoints.py \
       test/unit/common/middleware/test_listing_formats.py \
+      test/unit/common/middleware/test_memcache.py \
       test/unit/common/middleware/test_proxy_logging.py \
       test/unit/common/middleware/test_tempauth.py \
       test/unit/common/ring \