@property<EOL><INDENT>def sixtofour(self):<DEDENT>
if (self._ip >> <NUM_LIT>) != <NUM_LIT>:<EOL><INDENT>return None<EOL><DEDENT>return IPv4Address((self._ip >> <NUM_LIT>) & <NUM_LIT>)<EOL>
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.