Contao\System::__construct PHP Méthode

    protected function __construct()
    {
        $this->import('Config');
    }

 /**
  * Constructor
  */
 public function __construct()
 {
     parent::__construct();
     $this->import('Database');
     $this->import('Input');
     $this->database = $this->Database;
     $this->input = $this->Input;
 }