Learning to Code with Python: Lesson 2.2 Simple Animation

from tkinter import *
import random
import time

tk = Tk()
canvas = Canvas(tk, width=500, heigh=400)
tk.title("drawing")
canvas.pack()

ball = canvas.create_oval(10, 10, 60, 60, fill="orange")
xspeed = 1yspeed = 1
while True:
    canvas.move(ball, xspeed, yspeed)
    pos = canvas.coords(ball)
    if pos[3] >= 400 or pos[1] <=0:
        yspeed = -yspeed
    if pos[2] >= 500 or pos[0] <= 0:
        xspeed = -xspeed
    tk.update()
    time.sleep(0.01)
tk.mainloop()