from turtle import*
def moveto(x,y):
    penup()
    goto(x,y)
    pendown()
def main():
    setup(800,600)
    speed(0)
    for radius in range(20,200,20):
        moveto(0,-radius)
        circle(radius)
    hideturtle()
    done()
if __name__=='__main__':
    main()

　　

from turtle import *
def moveto(x,y):
    penup()
    goto(x,y)
    pendown()
def main():
    setup(800, 600)
    speed(0)
    for radius in range(180, 0, -20):
        moveto(0, -radius)
        circle(radius)
    hideturtle()
    done()
if __name__ == '__main__':
    main()

　

from turtle import *
from random import random
def moveto(x,y):
    penup()
    goto(x,y)
    pendown()
def main():
    setup(800, 600)
    speed(0)
    for radius in range(180, 0, -20):
        moveto(0, -radius)
        rgb = tuple(random() for i in range(3))
        color(rgb)
        begin_fill()
        circle(radius)
        end_fill()
    hideturtle()
    done()

if __name__ == '__main__':
    main()

　　

from turtle import *
def square(size=50, rgb = 'orange'):
    pencolor(rgb)
    for i in range(4):
        fd(size)
        left(90)
def main():
    setup(800, 600)
    speed(0)
    for i in range(3):
        square(80)
        left(120)
    hideturtle()
    done()
if __name__ == '__main__':
    main()

　　

from turtle import *
setup(800, 600)
pencolor('pink')
for i in range(4):
    for i in range(2):
        circle(80, 90)
        left(90)
    right(90)
hideturtle()
done()

　　

from turtle import *
speed(0)
setup(800, 600)
bgcolor('black')
pencolor('white')
angle = 0
size = 2
for i in range(10):
    for j in range(4):
        fd(size)
        angle += 91
        seth(angle)
        size += 5
hideturtle()
done()

　　

 

from turtle import*
from random import random
def  moveto(x,y):
    penup()
    goto(x,y)
    pendown()
def square(size = 50):
    for i in range(2):
        fd(0.5*size)
        left(90)
        fd(size)
        left(90)
def main():
    for x in range(-200,200,20):
        moveto(x,0)
        rgb = tuple(random() for i in range(3))
        color(rgb)
        begin_fill()
        square()
        end_fill()
        speed(0)
    hideturtle()
    done()
if __name__ == '__main__':
    main()