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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 _getMyFirstDatetimeTo(self):
 """ The datetime this event first finished, or None if it never did. """

        myFirstDt = self._getMyFirstDatetimeFrom()
        if myFirstDt is not None:
            daysDelta = dt.timedelta(days=self.num_days - 1)
            return getAwareDatetime(myFirstDt.date() + daysDelta,
                                    self.time_to,
                                    self.tz, dt.time.max)