def _backfill(self):
        log.info("Extended API backfill called")

        body = request.get_json()
        try:
            command_list, username = backfillDAGRunSchema.load(body)
        except ValidationError as err:
            raise BadRequest(detail=str(err.messages))

        # For backfilling: API will get 504 Gateway Time-out due to taking time to finish
        # output = execute_cli_command(command_list, username)
        # result = commandExecutionResult.load(output)

        thread = threading.Thread(target=execute_cli_command, args=(command_list, username))
        thread.start()

        return {"message": "Backfill operation started"}, 202