tkinter时钟（实时更新显示）

from tkinter import *
import time

root = Tk()
root.geometry('300x200')

var = StringVar()

def show():
    global var
    text = time.strftime('%Y-%m-%d %H:%M:%S')
    root.after(1000, show)
    var.set(text)

show()

Label(root,textvariable=var).pack()

root.mainloop()