from turtle import *
 
def yin(radius = 100, fyin = "white", fpunkt = "black"):
    fillcolor(fyin)
    begin_fill()
    circle(radius/2, -180)
    right(180)
    circle(radius/2, 180)
    circle(radius, 180)
    end_fill()
    left(90)
    penup()
    forward(radius + radius/2 - radius/8)
    right(90)
    pendown()
    fillcolor(fpunkt)
    begin_fill()
    circle(radius/8)
    end_fill()
 
radius = 200
reset()
pensize = 3
yin(radius)
penup()
left(90)
forward(radius/2 + radius/8)
left(90)
pendown()
yin(radius, "black", "white")
hideturtle()

Und noch eine Version (2019)

from turtle import *
 
def jump(laenge, winkel=0):
    """Springt laenge Pixel"""
    penup()
    left(winkel)
    forward(laenge)
    pendown()
 
def yinyang(radius, farbe, gegenfarbe):
    fillcolor(farbe)
    begin_fill()
    circle(radius/2, 180)
    circle(radius, 180)
    left(180)
    circle(-radius/2, 180)
    end_fill()
    jump(radius/2, 90)
    dot(radius/4, gegenfarbe)
 
radius = 300
yinyang(radius, 'white', 'black')
left(180)
jump(radius /2)
left(270)
yinyang(radius, 'black','white')
hideturtle()