import fractals
import math

def F(turtle):
    turtle.move()

def plus(turtle):
    turtle.turn(2 * math.pi / 3)

def minus(turtle):
    turtle.turn(-2 * math.pi / 3)
    
def terdragon(n):
    f = fractals.Fractal([F], {F:[F,plus,F,minus,F]})
    fractals.render(f, n, size=(500,400))