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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_clock_time(cls, clock_time, epoch):
 """ Convert from a ClockTime relative to a given epoch. """

        try:
            clock_time = ClockTime(*clock_time)
        except (TypeError, ValueError):
            raise ValueError("Clock time must be a 2-tuple of (s, ns)")
        else:
            ordinal = clock_time.seconds // 86400
            return Date.from_ordinal(ordinal + epoch.date().to_ordinal())