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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 fromordinal(cls, ordinal):
 """Return the week corresponding to the proleptic Gregorian ordinal, where January 1 of year 1 starts the week with ordinal 1. """

        if ordinal < 1:
            raise ValueError("ordinal must be >= 1")
        return super(Week, cls).__new__(cls, *(date.fromordinal((ordinal-1) * 7 + 1).isocalendar()[:2]))