As the title states, how do I stop the images in an animation made in tkinter from disappearing?

I have my code here:

ballx1 = 100
bally1 = 500
speed=10

for frames in range(300):
    rectangle = s.create_rectangle(ballx1,bally1,ballx1+100,bally1+200,fill='red')
    s.update()
    sleep(0.0333)
    s.delete(rectangle)
    if(bally1 >= 600):
        speed=speed * -1
    if bally1<=0:
        speed=speed * -1
    bally1=bally1-speed

How would I prevent the screen from going black at the end of the loop?

I have attempted altering the delete line to this,

if frames<=299:
        s.delete(rectangle)

, but the screen still goes black in the end.