public static function load_current_activity()
 {
     global $post;
     if (isset($post)) {
         return AC::load_activity_meta($post->ID);
     }
     if (get_the_ID()) {
         return AC::load_activity_meta(get_the_ID());
     }
     if (isset($_SESSION['edgimo-reservation-form']['post_id'])) {
         return AC::load_activity_meta($_SESSION['edgimo-reservation-form']['post_id']);
     }
     return false;
 }