protected function execute(InputInterface $input, OutputInterface $output)
 {
     $aantal = $input->getArgument('aantal');
     $return = '';
     if (!$aantal) {
         $aantal = 30;
     }
     for ($i = 0; $i < $aantal; $i++) {
         $em = $this->getContainer()->get('doctrine.orm.entity_manager');
         $faker = Factory::create();
         $monitoring = new Monitoring();
         $monitoring->setUnitId($faker->randomNumber());
         $monitoring->setType($this->getRealMonitoringType());
         $monitoring->setBeginTime($faker->dateTime());
         $monitoring->setEndTime($faker->dateTime());
         $monitoring->setDate($faker->dateTime());
         $monitoring->setCreatedAt($faker->dateTime());
         $monitoring->setUpdatedAt($faker->dateTime());
         $monitoring->setMin($faker->randomNumber());
         $monitoring->setMax($faker->randomNumber());
         $monitoring->setSum($faker->randomNumber());
         if ($em->persist($monitoring)) {
             $aantal--;
             echo $monitoring->getId();
         }
         $em->flush();
     }
 }