diff --git a/synapse/storage/media_repository.py b/synapse/storage/media_repository.py
index 2eb2740d07..84b5f3ad5e 100644
--- a/synapse/storage/media_repository.py
+++ b/synapse/storage/media_repository.py
@@ -16,7 +16,6 @@ from synapse.storage.background_updates import BackgroundUpdateStore
 
 
 class MediaRepositoryBackgroundUpdateStore(BackgroundUpdateStore):
-
     def __init__(self, db_conn, hs):
         super(MediaRepositoryBackgroundUpdateStore, self).__init__(db_conn, hs)
 
diff --git a/synapse/storage/search.py b/synapse/storage/search.py
index 9a41e78002..6ba4190f1a 100644
--- a/synapse/storage/search.py
+++ b/synapse/storage/search.py
@@ -337,7 +337,6 @@ class SearchBackgroundUpdateStore(BackgroundUpdateStore):
 
 
 class SearchStore(SearchBackgroundUpdateStore):
-
     def __init__(self, db_conn, hs):
         super(SearchStore, self).__init__(db_conn, hs)
 
diff --git a/synapse/storage/state.py b/synapse/storage/state.py
index 71b533c006..a941a5ae3f 100644
--- a/synapse/storage/state.py
+++ b/synapse/storage/state.py
@@ -1288,7 +1288,9 @@ class StateGroupWorkerStore(
         return self.runInteraction("store_state_group", _store_state_group_txn)
 
 
-class StateBackgroundUpdateStore(StateGroupBackgroundUpdateStore, BackgroundUpdateStore):
+class StateBackgroundUpdateStore(
+    StateGroupBackgroundUpdateStore, BackgroundUpdateStore
+):
 
     STATE_GROUP_DEDUPLICATION_UPDATE_NAME = "state_group_state_deduplication"
     STATE_GROUP_INDEX_UPDATE_NAME = "state_group_state_type_index"