code: def get_calendar_holidays(self, year):
          
          # Unshifted days are here:
          days = super(ChineseNewYearCalendar, self).get_calendar_holidays(year)
          if self.shift_sunday_holidays:
              days_to_inspect = copy(days)
              for day_shifted in self.get_shifted_holidays(days_to_inspect):
                  days.append(day_shifted)
          return days
docs: Take into account the eventual shift to the next MON if any holiday
          falls on SUN.