1 files changed, 3 insertions, 2 deletions
diff --git a/synapse/push/httppusher.py b/synapse/push/httppusher.py
index f4d7e199e9..eb6de8ba72 100644
--- a/synapse/push/httppusher.py
+++ b/synapse/push/httppusher.py
@@ -15,11 +15,12 @@
 # limitations under the License.
 import logging
 import urllib.parse
-from typing import TYPE_CHECKING, Any, Dict, Iterable, Union
+from typing import TYPE_CHECKING, Any, Dict, Iterable, Optional, Union
 
 from prometheus_client import Counter
 
 from twisted.internet.error import AlreadyCalled, AlreadyCancelled
+from twisted.internet.interfaces import IDelayedCall
 
 from synapse.api.constants import EventTypes
 from synapse.events import EventBase
@@ -71,7 +72,7 @@ class HttpPusher(Pusher):
         self.data = pusher_config.data
         self.backoff_delay = HttpPusher.INITIAL_BACKOFF_SEC
         self.failing_since = pusher_config.failing_since
-        self.timed_call = None
+        self.timed_call = None  # type: Optional[IDelayedCall]
         self._is_processing = False
         self._group_unread_count_by_room = hs.config.push_group_unread_count_by_room
         self._pusherpool = hs.get_pusherpool()