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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 teredo(self):
 """Tuple of embedded teredo IPs. Returns: Tuple of the (server, client) IPs or None if the address doesn't appear to be a teredo address (doesn't start with 2001::/32) """

        if (self._ip >> 96) != 0x20010000:
            return None
        return (IPv4Address((self._ip >> 64) & 0xFFFFFFFF),
                IPv4Address(~self._ip & 0xFFFFFFFF))