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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 week_date(self, start: int = 2017, end: int = 2018) -> str: """Get week number with year. :param start: From start. :param end: To end. :return: Week number. """

        year = self.year(start, end)
        week = self.random.randint(1, 52)
        return '{year}-W{week}'.format(
            year=year,
            week=week,
        )