diff --git a/synapse/handlers/e2e_room_keys.py b/synapse/handlers/e2e_room_keys.py
index 117144bb6eb3e485b88aa1b8a12c4e9e17252903..bf2a83cc31c968b104fb54b9722ebc4d0ec2f14c 100644
--- a/synapse/handlers/e2e_room_keys.py
+++ b/synapse/handlers/e2e_room_keys.py
@@ -16,6 +16,7 @@
 import logging
 
 from six import iteritems
+
 from twisted.internet import defer
 
 from synapse.api.errors import RoomKeysVersionError, StoreError, SynapseError