code: public String model() throws CommandExecutionException {
          JSONObject in = info();
          if (in == null) throw new CommandExecutionException(CommandExecutionException.Error.INVALID_RESPONSE);
          return in.optString("model");
      }
docs: Get the devices model id.
  @return The devices model id.
  @throws CommandExecutionException When there has been a error during the communication or the response was invalid.