说明：  创建VI，在前面板放置３个圆形LED，程序运行时，第一个灯打开并保持打开状态，１秒后第二个灯打开并保持打开状态，再过２秒第三个灯打开并保持打开状态，所有灯都保持打开状态3秒后熄灭。
(Create VI, place three circular led on the front panel. When the program is running, the first lamp is on and remains on, the second lamp is on and remains on after 1 second, and the third lamp is on and remains on after 2 seconds. All lights are kept on for 3 seconds and then go out.)