Python 2.2 (#1, May 14 2002, 18:23:13) 
[GCC 2.95.3 20010315 (SuSE)]
PyShell 1.1 

[In 16]:
import turtle as t
from math import *
[Out 16]:
[In 67]:
def dendron(l, iter):
    l1 = l/2.
    l2 = l1*1.1 
    angle = 50

    if iter > 0:
        t.forward(l1)
        t.left(angle)
        dendron(l2, iter-1)
        t.right(2*angle)
        dendron(l2, iter-1)
        t.left(angle)
        t.backward(l1)
    else:
        t.forward(l1)
        t.left(angle)
        t.forward(l2)
        t.backward(l2)
        t.right(angle*2)
        t.forward(l2)
        t.backward(l2)
        t.left(angle)
        t.backward(l1)
[Out 67]:
[In 68]:
t.create_pen(doc)
[Out 68]:
[In 71]:
doc.SelectNone()
dendron(100, 7)
[Out 71]:
>