code: public function prepend(ContainerBuilder $container, array $config)
      {
          if (false === array_key_exists($this->getName(), $config)) {
              return;
          }
  
          foreach ($config[$this->getName()] as $id => $section) {
              $config = $this->createServiceConfiguration($config, $id, $section);
          }
  
          return $config;
      }
docs: {@inheritdoc}