# -*- coding: utf-8 -*-
import turtle
win = turtle.Screen()
win.setup(1.0,1.0)
######

def tree(branchLen, t):
    
    if branchLen <= 30:
        t.pensize(3)
        t.pencolor('green')
    else:
        t.pensize(1)
        t.pencolor('black')
        
    if branchLen>5:
        t.fd(branchLen)
        t.right(20)
        tree(branchLen-15, t)
        t.left(40)
        tree(branchLen-15, t)
        t.right(20)
        t.up()
        t.bk(branchLen)
        t.down()
        
tt = turtle.Turtle()
tt.speed(0)
tt.up()
tt.left(90)
tt.sety(-350)
tt.down()
tree(70, tt)

######
win.exitonclick()