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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 scheduled_event_trigger(self, event_type):
 """Returns a callback that schedules events for the future. Returned callback function will add an event of type event_type to a queue which will be checked the next time an event is requested."""

        def callback(when, **kwargs):
            self.queued_scheduled_events.append((when, event_type(when=when, **kwargs)))
        return callback