When Christmas and/or Boxing Day falls on a weekend, it is rolled
            forward to the next weekday.

def shift_christmas_boxing_days(self, year):
        """ When Christmas and/or Boxing Day falls on a weekend, it is rolled
            forward to the next weekday.
        """
        christmas = date(year, 12, 25)
        boxing_day = date(year, 12, 26)
        boxing_day_label = "{} Shift".format(self.boxing_day_label)
        results = []
        if christmas.weekday() in self.get_weekend_days():
            shift = self.find_following_working_day(christmas)
            results.append((shift, "Christmas Shift"))
            results.append((shift + timedelta(days=1), boxing_day_label))
        elif boxing_day.weekday() in self.get_weekend_days():
            shift = self.find_following_working_day(boxing_day)
            results.append((shift, boxing_day_label))
        return results