import turtle as t
#画一个太极图
def yuan(radius,extent = None,steps = None,x=0,y=0,fc='white'):
t.up()
t.goto(x,y-radius)
t.down()
t.fillcolor(fc)
t.begin_fill()
t.circle( radius, extent, steps )
t.end_fill()
t.up()
t.goto(x,y)
t.setheading(0)
t.down
t.clear()
yuan(200,extent=180,fc='black')
yuan(200,extent=-180)
yuan(100,extent=-180,y=-100,fc='black')
yuan(100,extent=180,y=100)
yuan(30,y=-100)
yuan(30,y=100,fc='black')
t.done()