docs: def DeleteMessageHandlerRequests(self, requests, cursor=None):
      """Deletes a list of message handler requests from the database."""
  
      query = "DELETE FROM message_handler_requests WHERE request_id IN ({})"
      request_ids = set([r.request_id for r in requests])
      query = query.format(",".join(["%s"] * len(request_ids)))
      cursor.execute(query, request_ids)