# GrowingCircle.py

# GrowingCircle.py

from Tkinter import *

w=640
h=640
root = Tk()
canvas = Canvas(root, width=w, height=h, bg="black")
canvas.grid()
root.wm_title("Growing Circle")

def _create_circle(self, x, y, r, **kwargs):
    return self.create_oval(x-r, y-r, x+r, y+r, **kwargs)
Canvas.create_circle = _create_circle

while 1:
    for z in range(5,320):
        canvas.create_circle(w/2, h/2, z, fill="black", outline="white", width=2)
        canvas.update()
        canvas.create_circle(w/2, h/2, z, fill="black", outline="black", width=2)

root.mainloop()