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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 from_week(cls, year, iso_week):
 """ Create ``daterange`` based on a year and an ISO week :param year: Year as an integer :param iso_week: ISO week number :return: A new ``daterange`` for the given week .. versionadded:: 0.4.0 """


        first_day = date_from_iso_week(year, iso_week)
        return cls.from_date(first_day, period="week")