#科赫雪花
import turtle
def koch(size, n):
if n == 0:
turtle.fd(size)
else:
for angle in[0,60,-120,60]:
turtle.left(angle)
koch(size/3,n-1)
def main():
turtle.setup(600,600)
turtle.penup()
turtle.goto(-200,100)
turtle.pendown()
turtle.pensize(2)
level = 3
koch(400,level)
turtle.right(120)
koch(400,level)
turtle.right(120)
koch(400,level)
turtle.hideturtle()
main()
运行结果如下: