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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 omer_day(self):
 """Return the day of the Omer."""

        first_omer_day = HebrewDate(self.hdate.year, Months.Nisan, 16)
        omer_day = self._jdn - conv.hdate_to_jdn(first_omer_day) + 1
        if not 0 < omer_day < 50:
            return 0
        return omer_day