code: def redact_event(self, room_id, event_id, reason=None, txn_id=None, timestamp=None):
          
          if not txn_id:
              txn_id = self._make_txn_id()
  
          path = '/rooms/%s/redact/%s/%s' % (
              room_id, event_id, txn_id
          )
          content = {}
          if reason:
              content['reason'] = reason
          params = {}
          if timestamp:
              params["ts"] = timestamp
          return self._send("PUT", path, content, query_params=params)
docs: Perform PUT /rooms/$room_id/redact/$event_id/$txn_id/
  
          Args:
              room_id(str): The room ID to redact the message event in.
              event_id(str): The event id to redact.
              reason (str): Optional. The reason the message was redacted.
              txn_id(int): Optional. The transaction ID to use.
              timestamp(int): Optional. Set origin_server_ts (For application services only)