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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_hex(cls, value):
 """Initialize a new network from hexadecimal notation."""

        if len(value) == 8:
            return cls(int(value, 16))
        elif len(value) == 32:
            return cls(int(value, 16))
        else:
            raise ValueError('%r: invalid hexadecimal notation' % (value,))