def _read_proto_resolve(self, length, ptype):
<EOL>if ptype == '<STR_LIT>':     <EOL><INDENT>return ipaddress.ip_address(self._read_fileng(<NUM_LIT:4>))<EOL><DEDENT>elif ptype == '<STR_LIT>':   <EOL><INDENT>return ipaddress.ip_address(self._read_fileng(<NUM_LIT:16>))<EOL><DEDENT>else:<EOL><INDENT>return self._read_fileng(length)<EOL><DEDENT>
Resolve IP address according to protocol.

        Positional arguments:
            * length -- int, protocol address length
            * ptype -- int, protocol type

        Returns:
            * str -- IP address