code: public static function createBlock($type)
      {
          if (!array_key_exists($type, self::$blocks)) {
              throw new RuntimeException(
                  sprintf('The plugin %s is not registered: the block has not been created', $type)
              );
          }
  
          $class = self::$blocks[$type];
  
          return self::instantiateBlock($class);
      }
docs: {@inheritdoc}