def _makeHeaderUnix(sig=V2_SIGNATURE, verCom=b'\x21', famProto=b'\x31',
                    addrLength=b'\x00\xD8',
                    addrs=(b'\x2F\x68\x6F\x6D\x65\x2F\x74\x65\x73\x74\x73\x2F'
                           b'\x6D\x79\x73\x6F\x63\x6B\x65\x74\x73\x2F\x73\x6F'
                           b'\x63\x6B' + (b'\x00' * 82)) * 2):
    """
    Construct a version 2 IPv4 header with custom bytes.

    @param sig: The protocol signature; defaults to valid L{V2_SIGNATURE}.
    @type sig: L{bytes}

    @param verCom: Protocol version and command.  Defaults to V2 PROXY.
    @type verCom: L{bytes}

    @param famProto: Address family and protocol.  Defaults to AF_UNIX/STREAM.
    @type famProto: L{bytes}

    @param addrLength: Network-endian byte length of payload.  Defaults to 108
        bytes for 2 null terminated paths.
    @type addrLength: L{bytes}

    @param addrs: Address payload.  Defaults to C{/home/tests/mysockets/sock}
        for source and destination paths.
    @type addrs: L{bytes}

    @return: A packet with header, addresses, and8 ports.
    @rtype: L{bytes}
    """
    return sig + verCom + famProto + addrLength + addrs

    Construct a version 2 IPv4 header with custom bytes.

    @param sig: The protocol signature; defaults to valid L{V2_SIGNATURE}.
    @type sig: L{bytes}

    @param verCom: Protocol version and command.  Defaults to V2 PROXY.
    @type verCom: L{bytes}

    @param famProto: Address family and protocol.  Defaults to AF_UNIX/STREAM.
    @type famProto: L{bytes}

    @param addrLength: Network-endian byte length of payload.  Defaults to 108
        bytes for 2 null terminated paths.
    @type addrLength: L{bytes}

    @param addrs: Address payload.  Defaults to C{/home/tests/mysockets/sock}
        for source and destination paths.
    @type addrs: L{bytes}

    @return: A packet with header, addresses, and8 ports.
    @rtype: L{bytes}
    
stackoverflow/venv/lib/python3.6/site-packages/twisted/protocols/haproxy/test/test_v2parser.py