How to use the sshuttle.helpers.debug3 function in sshuttle

def test_debug3_nop(mock_stderr, mock_stdout):
    sshuttle.helpers.debug3("message")
    assert mock_stdout.mock_calls == []
    assert mock_stderr.mock_calls == []

def recv_udp(listener, bufsize):
        debug3('Accept UDP python using recvmsg.\n')
        data, ancdata, _, srcip = listener.recvmsg(4096,
                                                   socket.CMSG_SPACE(4))
        dstip = None
        for cmsg_level, cmsg_type, cmsg_data in ancdata:
            if cmsg_level == socket.SOL_IP and cmsg_type == IP_RECVDSTADDR:
                port = 53
                ip = socket.inet_ntop(socket.AF_INET, cmsg_data[0:4])
                dstip = (ip, port)
                break
        return (srcip, dstip, data)
elif recvmsg == "socket_ext":

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))

def dns_done(chan, data, method, sock, srcip, dstip, mux):
    debug3('dns_done: channel=%d src=%r dst=%r\n' % (chan, srcip, dstip))
    del mux.channels[chan]
    del dnsreqs[chan]
    method.send_udp(sock, srcip, dstip, data)

def try_connect(self):
        if self.connect_to and self.shut_write:
            self.noread()
            self.connect_to = None
        if not self.connect_to:
            return  # already connected
        self.rsock.setblocking(False)
        debug3('%r: trying connect to %r\n' % (self, self.connect_to))
        try:
            self.rsock.connect(self.connect_to)
            # connected successfully (Linux)
            self.connect_to = None
        except socket.error:
            _, e = sys.exc_info()[:2]
            debug3('%r: connect result: %s\n' % (self, e))
            if e.args[0] == errno.EINVAL:
                # this is what happens when you call connect() on a socket
                # that is now connected but returned EINPROGRESS last time,
                # on BSD, on python pre-2.5.1.  We need to use getsockopt()
                # to get the "real" error.  Later pythons do this
                # automatically, so this code won't run.
                realerr = self.rsock.getsockopt(socket.SOL_SOCKET,
                                                socket.SO_ERROR)
                e = socket.error(realerr, os.strerror(realerr))
                debug3('%r: fixed connect result: %s\n' % (self, e))
            if e.args[0] in [errno.EINPROGRESS, errno.EALREADY]:
                pass  # not connected yet
            elif e.args[0] == 0:
                # connected successfully (weird Linux bug?)
                # Sometimes Linux seems to return EINVAL when it isn't
                # invalid.  This *may* be caused by a race condition

def recv_udp(udp_listener, bufsize):
        debug3('Accept UDP using recvfrom.\n')
        data, srcip = udp_listener.recvfrom(bufsize)
        return (srcip, None, data)

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))

def try_connect(self):
        if self.connect_to and self.shut_write:
            self.noread()
            self.connect_to = None
        if not self.connect_to:
            return  # already connected
        self.rsock.setblocking(False)
        debug3('%r: trying connect to %r\n' % (self, self.connect_to))
        try:
            self.rsock.connect(self.connect_to)
            # connected successfully (Linux)
            self.connect_to = None
        except socket.error:
            _, e = sys.exc_info()[:2]
            debug3('%r: connect result: %s\n' % (self, e))
            if e.args[0] == errno.EINVAL:
                # this is what happens when you call connect() on a socket
                # that is now connected but returned EINPROGRESS last time,
                # on BSD, on python pre-2.5.1.  We need to use getsockopt()
                # to get the "real" error.  Later pythons do this
                # automatically, so this code won't run.
                realerr = self.rsock.getsockopt(socket.SOL_SOCKET,
                                                socket.SO_ERROR)
                e = socket.error(realerr, os.strerror(realerr))

assert(hw.pid > 0)
            (rpid, rv) = os.waitpid(hw.pid, os.WNOHANG)
            if rpid:
                raise Fatal(
                    'hostwatch exited unexpectedly: code 0x%04x\n' % rv)

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

        if dnshandlers:
            now = time.time()
            remove = []
            for channel, h in dnshandlers.items():
                if h.timeout < now or not h.ok:
                    debug3('expiring dnsreqs channel=%d\n' % channel)
                    remove.append(channel)
                    h.ok = False
            for channel in remove:
                del dnshandlers[channel]
        if udphandlers:
            remove = []
            for channel, h in udphandlers.items():
                if not h.ok:
                    debug3('expiring UDP channel=%d\n' % channel)
                    remove.append(channel)
                    h.ok = False
            for channel in remove:
                del udphandlers[channel]

def recv_udp(listener, bufsize):
        debug3('Accept UDP python using recvmsg.\n')
        data, ancdata, _, srcip = listener.recvmsg(
            4096, socket.CMSG_SPACE(24))
        dstip = None
        family = None
        for cmsg_level, cmsg_type, cmsg_data in ancdata:
            if cmsg_level == socket.SOL_IP and cmsg_type == IP_ORIGDSTADDR:
                family, port = struct.unpack('=HH', cmsg_data[0:4])
                port = socket.htons(port)
                if family == socket.AF_INET:
                    start = 4
                    length = 4
                else:
                    raise Fatal("Unsupported socket type '%s'" % family)
                ip = socket.inet_ntop(family, cmsg_data[start:start + length])
                dstip = (ip, port)
                break