import time
import math
import turtle
def line(startx,starty, endx,endy):
    fullx = endx-startx
    fully = endy-starty
    distance = math.sqrt(fully**2+fullx**2)
    if distance < 6:
        turtle.penup()
        turtle.goto(startx,starty)
        turtle.pendown()
        turtle.goto(endx,endy)
        return
    thirdx = fullx/3
    thirdy = fully/3
    Ax = startx+thirdx
    Ay = starty+thirdy
    Dx = endx-thirdx
    Dy = endy-thirdy
    Bx = Ax-thirdy
    By = Ay+thirdx
    Cx = Dx-thirdy
    Cy = Dy+thirdx
    line(startx,starty, Ax,Ay)
    line(Ax,Ay, Bx,By)
    line(Bx,By, Cx,Cy)
    line(Cx,Cy, Dx,Dy)
    line(Dx,Dy, endx,endy)

while True:
    turtle.ht()
    turtle.speed(0)
    turtle.pencolor("aqua")
    turtle.bgcolor("black")
    line(-600,-300,600,-300)
    time.sleep(10)
    turtle.reset()