final class Example extends Foo {
    const FOO='foo';

    public function __construct(
        public readonly string $name = self::FOO
    ) {}

    public function getClass(): string {
        return DateTimeImmutable::class;
    }

    public function getClassFromSelf(): string {
        return self::class;
    }

    public static function getClassFromStatic(): string {
        return static::class;
    }

    public static function getParentClass(): string {
        return parent::class;
    }
}

$date = DateTimeImmutable::createFromMutable(new \DateTime());
echo $date::class;