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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 event_at(self, when, data_tuple):
 """ Schedule an event to be emitted at a certain time. :param when: an absolute timestamp :param data_tuple: a 2-tuple (flavor, data) :return: an event object, useful for cancelling. """

        return self._base.event_at(when, self.make_event_data(*data_tuple))