LanguageSerializer example

private EntityRepository $languageRepository;

    private LanguageSerializer $serializer;

    private string $languageId = '1a9e90835a634ffd900b5a441251f551';

    protected function setUp(): void
    {
        $this->languageRepository = $this->getContainer()->get('language.repository');
        $serializerRegistry = $this->getContainer()->get(SerializerRegistry::class);

        $this->serializer = new LanguageSerializer($this->languageRepository);
        $this->serializer->setRegistry($serializerRegistry);
    }

    public function testSimple(): void
    {
        $this->createCountry();

        $config = new Config([], [], []);
        $language = [
            'locale' => [
                'code' => 'xx-XX',
            ],