/**
  * Create the CommandAssistant.
  *
  * @param InputInterface $input
  * @param OutputInterface $output
  */
 private function setInputAndOutput(InputInterface $input, OutputInterface $output)
 {
     if (is_null($this->assistant)) {
         $this->assistant = new CommandAssistant();
         $this->assistant->setDialog($this->getDialogHelper());
         $this->assistant->setKernel($this->getApplication()->getKernel());
     }
     $this->assistant->setOutput($output);
     $this->assistant->setInput($input);
 }