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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 _rollback_to_year(self, other):
 """ Roll `other` back to the most recent date that was on a fiscal year end. Return the date of that year-end, the number of full quarters elapsed between that year-end and other, and the remaining Timedelta since the most recent quarter-end. Parameters other : datetime or Timestamp Returns ------- tuple of prev_year_end : Timestamp giving most recent fiscal year end num_qtrs : int tdelta : Timedelta """

        num_qtrs = 0

        norm = Timestamp(other).tz_localize(None)
        start = self._offset.rollback(norm)
        # Note: start <= norm and self._offset.onOffset(start)

        if start < norm:
            # roll adjustment
            qtr_lens = self.get_weeks(norm)

            # check thet qtr_lens is consistent with self._offset addition
            end = liboffsets.shift_day(start, days=7 * sum(qtr_lens))
            assert self._offset.onOffset(end), (start, end, qtr_lens)

            tdelta = norm - start
            for qlen in qtr_lens:
                if qlen * 7 <= tdelta.days:
                    num_qtrs += 1
                    tdelta -= Timedelta(days=qlen * 7)
                else:
                    break
        else:
            tdelta = Timedelta(0)

        # Note: we always have tdelta.value >= 0
        return start, num_qtrs, tdelta