from DrawingPanel import *

def main():
    x = 20
    y = 50
    dx = 4
    panel = DrawingPanel(400, 400)
    while True:
        panel.clear()
        panel.fill_oval(x, y, 20, 20, fill="red")
        panel.sleep(20)
        x += dx
        y += 1
        if x + 20 >= panel.width or x <= 0:
            dx = -dx

main()