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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _execute_callback(self, status, message, job, res, err, stacktrace):
 """Execute the callback. :param status: Job status. Possible values are "invalid" (job could not be deserialized or was malformed), "failure" (job raised an error), "timeout" (job timed out), or "success" (job finished successfully and returned a result). :type status: str :param message: Kafka message. :type message: :doc:`kq.Message <message>` :param job: Job object, or None if **status** was "invalid". :type job: kq.Job :param res: Job result, or None if an exception was raised. :type res: object | None :param err: Exception raised by job, or None if there was none. :type err: Exception | None :param stacktrace: Exception traceback, or None if there was none. :type stacktrace: str | None """

        if self._callback is not None:
            try:
                self._logger.info('Executing callback ...')
                self._callback(status, message, job, res, err, stacktrace)
            except Exception as e:
                self._logger.exception(
                    'Callback raised an exception: {}'.format(e))