diff --git a/synapse/handlers/stats.py b/synapse/handlers/stats.py
index f065d88a7d..2f7c108181 100644
--- a/synapse/handlers/stats.py
+++ b/synapse/handlers/stats.py
@@ -219,9 +219,8 @@ class StatsHandler(StateDeltasHandler):
                 user_id = state_key
                 if self.is_mine_id(user_id):
                     # this accounts for transitions like leave → ban and so on.
-                    has_changed_joinedness = (
-                        (prev_membership == Membership.JOIN) !=
-                        (membership == Membership.JOIN)
+                    has_changed_joinedness = (prev_membership == Membership.JOIN) != (
+                        membership == Membership.JOIN
                     )
 
                     if has_changed_joinedness:
diff --git a/synapse/storage/stats.py b/synapse/storage/stats.py
index 6832ec6b7f..f86e9bd269 100644
--- a/synapse/storage/stats.py
+++ b/synapse/storage/stats.py
@@ -15,12 +15,9 @@
 # limitations under the License.
 
 import logging
+from itertools import chain
 from threading import Lock
 
-from twisted.internet import defer
-from itertools import chain
-
-from synapse.storage.state_deltas import StateDeltasStore
 from synapse.storage.state_deltas import StateDeltasStore
 from synapse.util.caches.descriptors import cached