static Map viber_setWebHook(S token, S url) {
  ret jsonDecodeMap(doPostJSONWithHeaders(
    jsonEncode(litmap(
      +url,
      send_name := "true",
      send_photo := "true")),
    "https://chatapi.viber.com/pa/set_webhook",
    "X-Viber-Auth-Token" := token));
}