public function createCity($nom, $reference, $postal)
 {
     $city = new City();
     $city->setNom($nom);
     $city->setDepartement($reference);
     $city->setPostal($postal);
     return $city;
 }
 public function createCity($nom, $reference, $postal)
 {
     $city = new City();
     $city->setNom($nom);
     $city->setDepartement($reference);
     $city->setPostal($postal);
     if ($nom == 'Rians') {
         $this->addReference('ville-rians', $city);
     }
     return $city;
 }