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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 add_listener(self, callback, mask=EVENT_ALL):
 """ Add a listener for scheduler events. When a matching event occurs, ``callback`` is executed with the event object as its sole argument. If the ``mask`` parameter is not provided, the callback will receive events of all types. For further info: https://apscheduler.readthedocs.io/en/latest/userguide.html#scheduler-events :param callback: any callable that takes one argument :param int mask: bitmask that indicates which events should be listened to """

        self._scheduler.add_listener(callback, mask)