Python Trying to turn this tree drawing program into a recus

(Python) Trying to turn this tree drawing program into a recusive tree drawing program. Make two recursive calls in drawtree with smaller length and width. Let the same program deal with how the smaller trees are drawn.

import turtle

def drawtree(length, w, t):
   def drawbranch(length, w, t):
       t.width(w)
       t.forward(length)

   drawbranch(length, w, t)
   t.left(45)
   drawbranch(length * 0.6, w * 0.6, t)
   t.backward(length * 0.6)
   t.right(90)
   drawbranch(length * 0.6, w * 0.6, t)
   t.backward(length * 0.6)
   t.left(45)
   t.backward(length)

def main():
   t = turtle.Turtle()
   screen = t.getscreen()
   t.goto(0, -200)
   t.speed(100)
   t.seth(90)
   drawtree(200, 20, t)
   screen.exitonclick()

Solution

import turtle

myTurtle = turtle.Turtle()
myWin = turtle.Screen()

def drawSpiral(myTurtle, lineLen):
    if lineLen > 0:
        myTurtle.forward(lineLen)
        myTurtle.right(90)
        drawSpiral(myTurtle,lineLen-5)

drawSpiral(myTurtle,100)
myWin.exitonclick()