public function setNew(string $new = "T") : CNabuDataObject
    {
        if ($new === null) {
            throw new ENabuCoreException(
                    ENabuCoreException::ERROR_NULL_VALUE_NOT_ALLOWED_IN,
                    array("\$new")
            );
        }
        $this->setValue('nb_user_group_member_new', $new);
        
        return $this;
    }