Add doc to get_event

synapse/storage/__init__.py

@@ -131,6 +131,21 @@ class DataStore(RoomMemberStore, RoomStore,
     def get_event(self, event_id, check_redacted=True,
                   get_prev_content=False, allow_rejected=False,
                   allow_none=False):
+        """Get an event from the database by event_id.
+
+        Args:
+            event_id (str): The event_id of the event to fetch
+            check_redacted (bool): If True, check if event has been redacted
+                and redact it.
+            get_prev_content (bool): If True and event is a state event,
+                include the previous states content in the unsigned field.
+            allow_rejected (bool): If True return rejected events.
+            allow_none (bool): If True, return None if no event found, if
+                False throw an exception.
+
+        Returns:
+            Deferred : A FrozenEvent.
+        """
         event = yield self.runInteraction(
             "get_event", self._get_event_txn,
             event_id,