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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_shifted_holidays(self, dates):
 """ Taking a list of existing holidays, yield a list of 'shifted' days if the holiday falls on SUN. """

        for holiday, label in dates:
            if holiday.weekday() == SUN:
                yield (
                    holiday + timedelta(days=1),
                    label + ' shift'
                )