2. 实现以鼠标单击控制的秒表程序，计时结果以“段码屏字体”显示，运用turtle；

以下是一个使用turtle库实现的以鼠标单击控制的秒表程序，计时结果以“段码屏字体”显示：

import turtle
import time

# 定义全局变量
start = 0  # 开始时间
running = False  # 计时器状态

# 定义画笔
pen = turtle.Turtle()
pen.hideturtle()

# 定义数字的段码字典
digit_segment = {'0': [(0, 1), (1, 0), (2, 0), (3, 1), (2, 2), (1, 2)],
                 '1': [(1, 0), (1, 2)],
                 '2': [(0, 1), (2, 1), (3, 1), (0, 2), (2, 2)],
                 '3': [(0, 1), (1, 0), (2, 1), (3, 1), (2, 2)],
                 '4': [(1, 0), (1, 1), (2, 1), (2, 2), (3, 2)],
                 '5': [(0, 1), (1, 0), (2, 1), (3, 1), (0, 2), (2, 2)],
                 '6': [(0, 1), (1, 0), (2, 0), (3, 1), (0, 2), (2, 2)],
                 '7': [(0, 0), (1, 0), (2, 1), (1, 2)],
                 '8': [(0, 1), (1, 0), (2, 0), (3, 1), (0, 2), (2, 2), (1, 1)],
                 '9': [(0, 1), (1, 0), (2, 1), (3, 1), (0, 2), (2, 2), (1, 1)]}


def draw_digit(digit, x, y):
    """
    绘制一个数字
    :param digit: 要绘制的数字
    :param x: 起始x坐标
    :param y: 起始y坐标
    """
    pen.penup()
    pen.goto(x, y)
    pen.pendown()
    for seg in digit_segment[digit]:
        x1, y1 = seg[0], seg[1]
        pen.goto(x + x1 * 10, y + y1 * 10)
    pen.penup()


def draw_time(t):
    """
    绘制时间
    :param t: 时间
    """
    # 分离出时分秒
    m, s = divmod(t, 60)
    h, m = divmod(m, 60)

    # 绘制小时
    draw_digit(str(h // 10), -100, 0)
    draw_digit(str(h % 10), -60, 0)

    # 绘制分钟
    draw_digit(str(m // 10), -20, 0)
    draw_digit(str(m % 10), 20, 0)

    # 绘制秒钟
    draw_digit(str(s // 10), 60, 0)
    draw_digit(str(s % 10), 100, 0)


def start_timer(x, y):
    """
    开始计时器
    """
    global start, running
    start = time.time()
    running = True


def stop_timer(x, y):
    """
    停止计时器
    """
    global start, running
    running = False
    elapsed = time.time() - start
    draw_time(elapsed)


# 注册鼠标单击事件
turtle.onscreenclick(start_timer, 1)
turtle.onscreenclick(stop_timer, 3)


# 循环绘制
while True:
    turtle.clear()
    draw_time(time.time() - start)
    turtle.update()
    time.sleep(0.1)

运行程序后，单击鼠标左键开始计时，单击右键停止计时，并将计时结果以“段码屏字体”显示在turtle窗口中。