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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 _parse_date(self, cell_value):
 """Attempts to parse a cell_value as a date."""

    date_tuple = xlrd.xldate_as_tuple(cell_value, self.raw_sheet.book.datemode)
    return self.tuple_to_datetime(date_tuple)