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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 get_variable_days(self, year):  # noqa
        "Return the christian holidays list according to the mixin"
        days = super(ChristianMixin, self).get_variable_days(year)
        if self.include_epiphany:
            days.append((date(year, 1, 6), "Epiphany"))
        if self.include_clean_monday:
            days.append((self.get_clean_monday(year), "Clean Monday"))
        if self.include_annunciation:
            days.append((date(year, 3, 25), "Annunciation"))
        if self.include_ash_wednesday:
            days.append(
                (self.get_ash_wednesday(year), self.ash_wednesday_label)
            )
        if self.include_palm_sunday:
            days.append((self.get_palm_sunday(year), "Palm Sunday"))
        if self.include_holy_thursday:
            days.append((self.get_holy_thursday(year), "Holy Thursday"))
        if self.include_good_friday:
            days.append((self.get_good_friday(year), self.good_friday_label))
        if self.include_easter_saturday:
            days.append((self.get_easter_saturday(year), "Easter Saturday"))
        if self.include_easter_sunday:
            days.append((self.get_easter_sunday(year), "Easter Sunday"))
        if self.include_easter_monday:
            days.append((self.get_easter_monday(year), "Easter Monday"))
        if self.include_assumption:
            days.append((date(year, 8, 15), "Assumption of Mary to Heaven"))
        if self.include_all_saints:
            days.append((date(year, 11, 1), "All Saints Day"))
        if self.include_all_souls:
            days.append((date(year, 11, 2), "All Souls Day"))
        if self.include_immaculate_conception:
            days.append((date(year, 12, 8), self.immaculate_conception_label))
        if self.include_christmas:
            days.append((date(year, 12, 25), "Christmas Day"))
        if self.include_christmas_eve:
            days.append((date(year, 12, 24), "Christmas Eve"))
        if self.include_boxing_day:
            days.append((date(year, 12, 26), self.boxing_day_label))
        if self.include_ascension:
            days.append((
                self.get_ascension_thursday(year), "Ascension Thursday"))
        if self.include_whit_monday:
            days.append((self.get_whit_monday(year), self.whit_monday_label))
        if self.include_whit_sunday:
            days.append((self.get_whit_sunday(year), self.whit_sunday_label))
        if self.include_corpus_christi:
            days.append((self.get_corpus_christi(year), "Corpus Christi"))
        return days