How to use the sshuttle.ssnet function in sshuttle

if not opt.sudoers_filename:
            log('--sudoers-file must be set or omited.')
            exit(1)

        sudoers(
            user_name=opt.sudoers_user,
            no_modify=opt.sudoers_no_modify,
            file_name=opt.sudoers_filename
        )

    if opt.daemon:
        opt.syslog = 1
    if opt.wrap:
        import sshuttle.ssnet as ssnet
        ssnet.MAX_CHANNEL = opt.wrap
    if opt.latency_buffer_size:
        import sshuttle.ssnet as ssnet
        ssnet.LATENCY_BUFFER_SIZE = opt.latency_buffer_size
    helpers.verbose = opt.verbose

    try:
        if opt.firewall:
            if opt.subnets or opt.subnets_file:
                parser.error('exactly zero arguments expected')
            return firewall.main(opt.method, opt.syslog)
        elif opt.hostwatch:
            return hostwatch.hw_main(opt.subnets, opt.auto_hosts)
        else:
            includes = opt.subnets + opt.subnets_file
            excludes = opt.exclude
            if not includes and not opt.auto_nets:

def udp_req(channel, cmd, data):
        debug2('Incoming UDP request channel=%d, cmd=%d\n' % (channel, cmd))
        if cmd == ssnet.CMD_UDP_DATA:
            (dstip, dstport, data) = data.split(b(','), 2)
            dstport = int(dstport)
            debug2('is incoming UDP data. %r %d.\n' % (dstip, dstport))
            h = udphandlers[channel]
            h.send((dstip, dstport), data)
        elif cmd == ssnet.CMD_UDP_CLOSE:
            debug2('is incoming UDP close\n')
            h = udphandlers[channel]
            h.ok = False
            del mux.channels[channel]

if line:
                name, ip = line.split(b',', 1)
                fw.sethostip(name, ip)
    mux.got_host_list = onhostlist

    tcp_listener.add_handler(handlers, onaccept_tcp, method, mux)

    if udp_listener:
        udp_listener.add_handler(handlers, onaccept_udp, method, mux)

    if dns_listener:
        dns_listener.add_handler(handlers, ondns, method, mux)

    if seed_hosts is not None:
        debug1('seed_hosts: %r\n' % seed_hosts)
        mux.send(0, ssnet.CMD_HOST_REQ, str.encode('\n'.join(seed_hosts)))

    while 1:
        rv = serverproc.poll()
        if rv:
            raise Fatal('server died with error code %d' % rv)

        ssnet.runonce(handlers, mux)
        if latency_control:
            mux.check_fullness()

exit(1)

        sudoers(
            user_name=opt.sudoers_user,
            no_modify=opt.sudoers_no_modify,
            file_name=opt.sudoers_filename
        )

    if opt.daemon:
        opt.syslog = 1
    if opt.wrap:
        import sshuttle.ssnet as ssnet
        ssnet.MAX_CHANNEL = opt.wrap
    if opt.latency_buffer_size:
        import sshuttle.ssnet as ssnet
        ssnet.LATENCY_BUFFER_SIZE = opt.latency_buffer_size
    helpers.verbose = opt.verbose

    try:
        if opt.firewall:
            if opt.subnets or opt.subnets_file:
                parser.error('exactly zero arguments expected')
            return firewall.main(opt.method, opt.syslog)
        elif opt.hostwatch:
            return hostwatch.hw_main(opt.subnets, opt.auto_hosts)
        else:
            includes = opt.subnets + opt.subnets_file
            excludes = opt.exclude
            if not includes and not opt.auto_nets:
                parser.error('at least one subnet, subnet file, '
                             'or -N expected')
            remotename = opt.remote

def expire_connections(now, mux):
    remove = []
    for chan, timeout in dnsreqs.items():
        if timeout < now:
            debug3('expiring dnsreqs channel=%d\n' % chan)
            remove.append(chan)
            del mux.channels[chan]
    for chan in remove:
        del dnsreqs[chan]
    debug3('Remaining DNS requests: %d\n' % len(dnsreqs))

    remove = []
    for peer, (chan, timeout) in udp_by_src.items():
        if timeout < now:
            debug3('expiring UDP channel channel=%d peer=%r\n' % (chan, peer))
            mux.send(chan, ssnet.CMD_UDP_CLOSE, b'')
            remove.append(peer)
            del mux.channels[chan]
    for peer in remove:
        del udp_by_src[peer]
    debug3('Remaining UDP channels: %d\n' % len(udp_by_src))

else:
            raise

    dstip = method.get_tcp_dstip(sock)
    debug1('Accept TCP: %s:%r -> %s:%r.\n' % (srcip[0], srcip[1],
                                              dstip[0], dstip[1]))
    if dstip[1] == sock.getsockname()[1] and islocal(dstip[0], sock.family):
        debug1("-- ignored: that's my address!\n")
        sock.close()
        return
    chan = mux.next_channel()
    if not chan:
        log('warning: too many open channels.  Discarded connection.\n')
        sock.close()
        return
    mux.send(chan, ssnet.CMD_TCP_CONNECT, b'%d,%s,%d' %
             (sock.family, dstip[0].encode("ASCII"), dstip[1]))
    outwrap = MuxWrapper(mux, chan)
    handlers.append(Proxy(SockWrapper(sock, sock), outwrap))
    expire_connections(time.time(), mux)

port = int(self.to_ns_port)

        family, sockaddr = self._addrinfo(peer, port)
        sock = socket.socket(family, socket.SOCK_DGRAM)
        sock.setsockopt(socket.SOL_IP, socket.IP_TTL, 42)
        sock.connect(sockaddr)

        self.peers[sock] = peer

        debug2('DNS: sending to %r:%d (try %d)\n' % (peer, port, self.tries))
        try:
            sock.send(self.request)
            self.socks.append(sock)
        except socket.error:
            _, e = sys.exc_info()[:2]
            if e.args[0] in ssnet.NET_ERRS:
                # might have been spurious; try again.
                # Note: these errors sometimes are reported by recv(),
                # and sometimes by send().  We have to catch both.
                debug2('DNS send to %r: %s\n' % (peer, e))
                self.try_send()
                return
            else:
                log('DNS send to %r: %s\n' % (peer, e))
                return

def callback(self, sock):
        try:
            data, peer = sock.recvfrom(4096)
        except socket.error:
            _, e = sys.exc_info()[:2]
            log('UDP recv from %r port %d: %s\n' % (peer[0], peer[1], e))
            return
        debug2('UDP response: %d bytes\n' % len(data))
        hdr = b("%s,%r," % (peer[0], peer[1]))
        self.mux.send(self.chan, ssnet.CMD_UDP_DATA, hdr + data)