修复刚刚代码的bug：Traceback (most recent call last): File "C:\Users\33438\AppData\Local\Temp\codemao-c4AYb6/temp.py", line 46, in <module> update_clock() File "C:\Users\33438\AppData\Local\Temp\codemao-c4AYb6/temp.py", line 41, in update_clock canvas.coords(hour_hand, 200, 200, 200 + 80 * round(2 * cos(radians(hour_angle))), 200 - 80 * round(2 * sin(radians(hour_angle)))) NameError: name 'cos' is not defined

这个错误说明你的代码中使用了一个未定义的函数 `cos()`。要使用 `cos()` 函数，需要先导入 math 模块。你可以在代码的开头添加 `import math`，然后在使用 `cos()` 函数的地方改为 `math.cos()`。你的代码应该像下面这样：

from tkinter import *
import datetime
import math

root = Tk()
root.geometry('400x400')

canvas = Canvas(root, width=400, height=400)
canvas.pack()

hour_hand = canvas.create_line(200, 200, 200, 120, width=5, fill='blue')
minute_hand = canvas.create_line(200, 200, 200, 80, width=3, fill='green')
second_hand = canvas.create_line(200, 200, 200, 40, width=1, fill='red')

def update_clock():
    now = datetime.datetime.now()
    hour = now.hour
    minute = now.minute
    second = now.second

    hour_angle = (hour % 12) * 30 + minute / 2
    minute_angle = minute * 6
    second_angle = second * 6

    canvas.coords(hour_hand, 200, 200, 200 + 80 * round(2 * math.cos(math.radians(hour_angle))), 200 - 80 * round(2 * math.sin(math.radians(hour_angle))))
    canvas.coords(minute_hand, 200, 200, 200 + 100 * round(2 * math.cos(math.radians(minute_angle))), 200 - 100 * round(2 * math.sin(math.radians(minute_angle))))
    canvas.coords(second_hand, 200, 200, 200 + 120 * round(2 * math.cos(math.radians(second_angle))), 200 - 120 * round(2 * math.sin(math.radians(second_angle))))

    root.after(1000, update_clock)

update_clock()

root.mainloop()

这样就可以消除这个错误了。