Doc args

synapse/storage/stream.py

@@ -247,6 +247,10 @@ class StreamStore(SQLBaseStore):
     def get_rooms_that_changed(self, room_ids, from_key):
         """Given a list of rooms and a token, return rooms where there may have
         been changes.
+
+        Args:
+            room_ids (list)
+            from_key (str): The room_key portion of a StreamToken
         """
         from_key = RoomStreamToken.parse_stream_token(from_key).stream
         return set(