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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 rosh_hashana_dow(self):
 """Return the Hebrew day of week for Rosh Hashana."""

        jdn = conv.hdate_to_jdn(HebrewDate(self.hdate.year, Months.Tishrei, 1))
        return (jdn + 1) % 7 + 1