public String ask(Tweet question) throws CloneNotSupportedException {
        
        String answer = "";
        Abo abo = new Abo(this.eleveur); 
            for(SmartCell cell:smartCells) {
                
                if (cell.ask(question, abo) != null)
                    answer = answer + cell.ask(question, abo) + " ";
              
            }
       if ("".equals(answer)){
           answer = "I don't understand your question.";
       }
       else{
           answer = answer.substring(0, answer.length()-1);
       }
       
       return answer;
    }