Часы

from tkinter import Tk, Canvas
import datetime, time
root = Tk()
canvas = Canvas(width = 400, height = 400, bg = 'deepskyblue')
canvas.pack()
today = datetime.datetime.now()
h = today.hour
m = today.minute
s = today.second
text = canvas.create_text(200,50,anchor = 'n',fill = 'orange', font = 'Verdana 20', text = 'Текущее время')
text_time = canvas.create_text(200,100,anchor = 'n',fill = 'green', font = 'Verdana 18', text = str(h)+' часов ' + str(m)+' мин '+str(s)+' сек ')
while True:
    today = datetime.datetime.now()
    h = today.hour
    m = today.minute
    s = today.second
    canvas.itemconfig(text_time, text = str(h)+' часов ' + str(m)+' мин '+str(s)+' сек ')
    root.update_idletasks() # эта и следующая строка очень важны, без них вы не увидите холст
    root.update()
    time.sleep(0.1)