static S smartBot_findMyExternalURL() {
  S ip = myFirewallIP();
  for (int port = 4678; port <= 4681; port++) {
    S url = "http://" + ip + ":" + port;
    print("Trying " + url);
    pcall-short { if (swic(loadPageWithTimeout(url + "/livecheck", 10000), "Smart Bot"))
      ret url;
    }
  }
  null;
}