add_shortcode("parentid", "parent_id");
function parent_id($atts) {
        global $wpdb;

        $current = $atts["id"];
        // Get current posts parent type
        $parentType = $wpdb->get_var("SELECT  `meta_key` FROM  `wp_postmeta` WHERE  `post_id` ={$current} AND `meta_key` LIKE '%belongs%'");

        // Get current posts parentID if project
        $parentID = $wpdb->get_var("SELECT  `meta_value` FROM  `wp_postmeta` WHERE  `post_id` ={$current} AND  `meta_key` =  '{$parentType}'" );
        return trim($parentID);

}