public static void Notify(INotificationChannel channel, INotificationReceiver receiver, NotificationContent content)
 {
     channel.Notify(receiver, content);
 }
 public void OrderVegetables(List <KeyValuePair <Vegetable, int> > insufficientVegetables)
 {
     // updating stock in the refrigerator
     _notificationChannel.Notify("Order Placed!");
 }