'Return the IPv4 6to4 embedded address.
Returns:
The IPv4 6to4-embedded address if present or None if the
address doesn\'t appear to contain a 6to4 embedded address.'

@property
def sixtofour(self):

    if ((self._ip >> 112) != 8194):
        return None
    return IPv4Address(((self._ip >> 80) & 4294967295))
