internal void Delete()
 {
     Deleting();
     CiscoObjectsWindow.DeleteFromTable(this);
     //lock (notifications)
     //{
     //    notifications.Remove(this);
     //}
     DeleteTime = DateTime.Now;
     CiscoObjectsWindow.EnableRestore(true);
 }
        static internal void RestoreLastDeleted()
        {
            CiscoObject n;

            lock (cisco_objects)
            {
                n = cisco_objects.Where(x => x.Deleted).OrderByDescending(x => x.DeleteTime).FirstOrDefault();
                if (n == null)
                {
                    CiscoObjectsWindow.EnableRestore(false);
                    return;
                }
            }
            n.DeleteTime = DateTime.MinValue;
            CiscoObjectsWindow.AddToTable(n);
            CiscoObjectsWindow.EnableRestore(cisco_objects.Where(x => x.Deleted).Count() > 0);
        }