# -*- coding: utf-8 -*-
import turtle
win = turtle.Screen()
win.setup(0.9,0.9)
######

def drawTree(n, ang, t):
    """Draw a Tree"""
    if n < 5:
        t.pencolor('green')
    else:
        t.pencolor('black')

    t.fd(n*15)
    if n == 0:
        pass
    else:
        t.left(ang)
        drawTree(n-1, ang, t)
        t.right(2*ang)
        drawTree(n-1, ang, t)
        t.left(ang)
    t.up()
    t.back(n*15)
    t.down()

tt = turtle.Turtle()
tt.up()
tt.sety(-350)
tt.left(90)
tt.pd()
drawTree(7, 20, tt)

######
win.exitonclick()