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

        myStartDt = getAwareDatetime(self.repeat.dtstart, None,
                                     self.tz, dt.time.min)
        return self.__after(myStartDt, excludeCancellations=False)