#!/usr/bin/python

"""       turtle-example-suite:

            tdemo_yinyang.py

Another drawing suitable as a beginner's

programming example.

The small circles are drawn by the circle

command.

"""

from turtle import *

def yin(radius, color1, color2):

    width(3)

    color("black")

    fill(True)

    circle(radius/2., 180)

    circle(radius, 180)

    left(180)

    circle(-radius/2., 180)

    color(color1)

    fill(True)

    color(color2)

    left(90)

    up()

    forward(radius*0.375)

    right(90)

    down()

    circle(radius*0.125)

    left(90)

    fill(False)

    up()

    backward(radius*0.375)

    down()

    left(90)

def main():

    reset()

    yin(200, "white", "black")

    yin(200, "black", "white")

    ht()

    return "Done!"

if __name__ == '__main__':

    main()

    mainloop()