code: public static function get(string $class)
      {
          if (isset(self::$controllers[$class]) === false) {
              self::$controllers[$class] = new $class();
          }
  
          return self::$controllers[$class];
      }
docs: Get a controller, creating one if it doesn't exist already.
  
  @static
  @param string $class controller class with namespace
  @return object controller