diff --git a/synapse/handlers/sliding_sync/extensions.py b/synapse/handlers/sliding_sync/extensions.py
index 2fc203281e..25ee954b7f 100644
--- a/synapse/handlers/sliding_sync/extensions.py
+++ b/synapse/handlers/sliding_sync/extensions.py
@@ -57,7 +57,7 @@ from synapse.util.async_helpers import (
 
 _ThreadSubscription: TypeAlias = (
     SlidingSyncResult.Extensions.ThreadSubscriptionsExtension.ThreadSubscription
-)  #
+)
 _ThreadUnsubscription: TypeAlias = (
     SlidingSyncResult.Extensions.ThreadSubscriptionsExtension.ThreadUnsubscription
 )