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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 calculate_equinoxes(self, year, timezone='UTC'):
 """ calculate equinox with time zone """


        tz = pytz.timezone(timezone)

        d1 = ephem.next_equinox(str(year))
        d = ephem.Date(str(d1))
        equinox1 = d.datetime() + tz.utcoffset(d.datetime())

        d2 = ephem.next_equinox(d1)
        d = ephem.Date(str(d2))
        equinox2 = d.datetime() + tz.utcoffset(d.datetime())

        return (equinox1.date(), equinox2.date())