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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 _calculate_timestamps(self):
 """Return a list of Ladybug DateTime in this analysis period."""

        self._timestamps_data = []
        if not self._is_reversed:
            self._calc_timestamps(self.st_time, self.end_time)
        else:
            self._calc_timestamps(self.st_time, DateTime.from_hoy(8759))
            self._calc_timestamps(DateTime.from_hoy(0), self.end_time)