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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 dates(self, start_date, end_date, return_name=False):
 """ Calculate holidays observed between start date and end date Parameters start_date : starting date, datetime-like, optional end_date : ending date, datetime-like, optional return_name : bool, optional, default=False If True, return a series that has dates and holiday names. False will only return dates. """

        start_date = Timestamp(start_date)
        end_date = Timestamp(end_date)

        filter_start_date = start_date
        filter_end_date = end_date

        if self.year is not None:
            dt = Timestamp(datetime(self.year, self.month, self.day))
            if return_name:
                return Series(self.name, index=[dt])
            else:
                return [dt]

        dates = self._reference_dates(start_date, end_date)
        holiday_dates = self._apply_rule(dates)
        if self.days_of_week is not None:
            holiday_dates = holiday_dates[np.in1d(holiday_dates.dayofweek,
                                                  self.days_of_week)]

        if self.start_date is not None:
            filter_start_date = max(self.start_date.tz_localize(
                filter_start_date.tz), filter_start_date)
        if self.end_date is not None:
            filter_end_date = min(self.end_date.tz_localize(
                filter_end_date.tz), filter_end_date)
        holiday_dates = holiday_dates[(holiday_dates >= filter_start_date) &
                                      (holiday_dates <= filter_end_date)]
        if return_name:
            return Series(self.name, index=holiday_dates)
        return holiday_dates