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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 netmask_long(self):
 """ Network netmask derived from subnet size, as long. 4278190080 """

        if self.version() == 4:
            return (MAX_IPV4 >> (32 - self.mask)) << (32 - self.mask)
        else:
            return (MAX_IPV6 >> (128 - self.mask)) << (128 - self.mask)