3: lst = [] for p in plist: p.forward(l) q = p.clone() p.left(a) q.right(a) lst.append(p) lst.append(q) for x in tree(lst, l*f, a, f): yield None def maketree(): p = Turtle() p.setundobuffer(None) p.hideturtle() p.speed(0) p.tracer(30,0) p.left(90) p.penup() p.forward(-210) p.pendown() t = tree([p], 200, 65, 0.6375) for x in t: pass print len(p.getscreen().turtles()) def main(): a=clock() maketree() b=clock() return "done: %.2f sec." % (b-a) if __name__ == "__main__": msg = main() print msg mainloop()