2 files changed, 5 insertions, 20 deletions
diff --git a/synapse/handlers/message.py b/synapse/handlers/message.py
index 9d0c38f4df..72bb638167 100644
--- a/synapse/handlers/message.py
+++ b/synapse/handlers/message.py
@@ -49,14 +49,7 @@ from synapse.metrics.background_process_metrics import run_as_background_process
 from synapse.replication.http.send_event import ReplicationSendEventRestServlet
 from synapse.storage.databases.main.events_worker import EventRedactBehaviour
 from synapse.storage.state import StateFilter
-from synapse.types import (
-    Collection,
-    Requester,
-    RoomAlias,
-    StreamToken,
-    UserID,
-    create_requester,
-)
+from synapse.types import Requester, RoomAlias, StreamToken, UserID, create_requester
 from synapse.util import json_decoder
 from synapse.util.async_helpers import Linearizer
 from synapse.util.frozenutils import frozendict_json_encoder
@@ -446,7 +439,7 @@ class EventCreationHandler(object):
         event_dict: dict,
         token_id: Optional[str] = None,
         txn_id: Optional[str] = None,
-        prev_event_ids: Optional[Collection[str]] = None,
+        prev_event_ids: Optional[List[str]] = None,
         require_consent: bool = True,
     ) -> Tuple[EventBase, EventContext]:
         """
@@ -786,7 +779,7 @@ class EventCreationHandler(object):
         self,
         builder: EventBuilder,
         requester: Optional[Requester] = None,
-        prev_event_ids: Optional[Collection[str]] = None,
+        prev_event_ids: Optional[List[str]] = None,
     ) -> Tuple[EventBase, EventContext]:
         """Create a new event for a local client
 
diff --git a/synapse/handlers/room_member.py b/synapse/handlers/room_member.py
index cae4d013b8..a7962b0ada 100644
--- a/synapse/handlers/room_member.py
+++ b/synapse/handlers/room_member.py
@@ -38,15 +38,7 @@ from synapse.events.builder import create_local_event_from_event_dict
 from synapse.events.snapshot import EventContext
 from synapse.events.validator import EventValidator
 from synapse.storage.roommember import RoomsForUser
-from synapse.types import (
-    Collection,
-    JsonDict,
-    Requester,
-    RoomAlias,
-    RoomID,
-    StateMap,
-    UserID,
-)
+from synapse.types import JsonDict, Requester, RoomAlias, RoomID, StateMap, UserID
 from synapse.util.async_helpers import Linearizer
 from synapse.util.distributor import user_joined_room, user_left_room
 
@@ -184,7 +176,7 @@ class RoomMemberHandler(object):
         target: UserID,
         room_id: str,
         membership: str,
-        prev_event_ids: Collection[str],
+        prev_event_ids: List[str],
         txn_id: Optional[str] = None,
         ratelimit: bool = True,
         content: Optional[dict] = None,