'Get the 802.3 MAC address from IPv6 RFC 2464 address, in lower case.
Return None if the address is an IPv4 or not a IPv6 RFC 2464 address.
>>> IP(\'fe80::f66d:04ff:fe47:2fae\').get_mac()
\'f4:6d:04:47:2f:ae\''

def get_mac(self):

    if (self._ipversion != 6):
        return None
    if ((self.ip & 144116287570706432) != 144116287553929216):
        return None
    return ('%02x:%02x:%02x:%02x:%02x:%02x' % ((((self.ip >> 56) & 255) & 253), ((self.ip >> 48) & 255), ((self.ip >> 40) & 255), ((self.ip >> 16) & 255), ((self.ip >> 8) & 255), (self.ip & 255)))
