///////// if used in the loop:
        if (!bank.isOpen()) { //Checking if bank has been opened correctly
                  bank.open(); //Opens bank
                  return 250; //It returns to the top after 250 ms, if the bank hasn't been opened yet it wil run bank.open(); again
          }else{ //if the bank has opened:
              //do stuff
          }
        ///////// if used in a boolean:
        if(!bank.isOpen()){
        for(int i=0;i<10&&!bank.isOpen();i++){ //change i to whatever you want
            bank.open();
            sleep(50);
        }
        }else{
            //do stuff
        }