src/Factory/Form/Element/BirthdayElementFactory.php
public function createService(ServiceLocatorInterface $serviceLocator)
    {
        $services = $serviceLocator->getServiceLocator();
        return $this->configureElement(new Birthday('birthday'), $services);
    }
public function createService(ServiceLocatorInterface $serviceLocator)
    {
        $services = $serviceLocator->getServiceLocator();
        return $this->configureElement(new Birthday('birthday'), $services);
    }
{@inheritDoc}

@return Birthday