/**
  * Retrieve the current session instance.
  *
  * @param bool $session_id Session ID from which to populate data.
  *
  * @return bool|RM_WP_Session
  */
 public static function get_instance()
 {
     if (!self::$instance) {
         self::$instance = new self();
     }
     return self::$instance;
 }
 /**
  * Write session data and end session
  */
 function wp_session_write_close()
 {
     $rm_session = RM_WP_Session::get_instance();
     $rm_session->write_data();
     do_action('wp_session_commit');
 }