docs: public VacuumTimer[] getTimers() throws CommandExecutionException {
          JSONArray tm = sendToArray("get_timer");
          if (tm == null) throw new CommandExecutionException(CommandExecutionException.Error.INVALID_RESPONSE);
          VacuumTimer[] timers = new VacuumTimer[tm.length()];
          for (int i = 0; i < tm.length(); i++){
              timers[i] = new VacuumTimer(tm.optJSONArray(i));
          }
          return timers;
      }