public function loadServices(ContainerBuilder $container)
    {
        $loader = new XmlFileLoader($container, new FileLocator(__DIR__ . '/config'));
        $loader->load('services.xml');
        $this->imageDrivers = $this->driverLocator->findDrivers(
            $container,
            $this->imageDriverKeys,
            $this->imageDriverConfigs
        );
    }