diff --git a/synapse/app/pusher.py b/synapse/app/pusher.py
index 6f5e7a2e3..d59922422 100644
--- a/synapse/app/pusher.py
+++ b/synapse/app/pusher.py
@@ -131,6 +131,10 @@ class PusherSlaveStore(
         DataStore.get_state_groups.__func__
     )
 
+    _get_state_group_for_events = (
+        DataStore._get_state_group_for_events.__func__
+    )
+
 
 class PusherServer(HomeServer):