programa de varias figuras en python

codigo:

import turtle
import tkSimpleDialog

turtle.speed(5)
fonde = turtle.Screen()
d=tkSimpleDialog.askstring("hola","Dame el grosor de pluma")
b=tkSimpleDialog.askstring("hola","Dame el color de pluma")
c=tkSimpleDialog.askstring("hola","Dame el color del fondo")
a=tkSimpleDialog.askstring("hola","Dame el color del relleno")
figura=tkSimpleDialog.askstring("hola","Ponga figura que desa realizar")
fonde.bgcolor(c)
turtle.pensize(d)
turtle.pencolor(b)
turtle.fillcolor(a)
turtle.begin_fill()

while(figura=="triangulo"):
    for x in range(3):
        turtle.forward(100)
        turtle.left(120)

    turtle.end_fill()

    turtle.exitonclick()

while (figura == "cuadrado"):
    for x in range(4):
        turtle.forward(100)
        turtle.left(90)

    turtle.end_fill()

    turtle.exitonclick()

while(figura=="rectangulo"):
    for x in range(2):
        turtle.forward(200)
        turtle.left(90)
        for x in range(1):
            turtle.forward(100)
            turtle.left(90)

    turtle.end_fill()

    turtle.exitonclick()

while (figura == "pentagono"):
    for x in range(5):
        turtle.forward(100)
        turtle.left(72)

    turtle.end_fill()

    turtle.exitonclick()

while (figura == "circulo"):
    for x in range(5):
        turtle.circle(130)

        turtle.end_fill()

        turtle.exitonclick()


while (figura == "octagono"):
    for x in range(8):
        turtle.forward(100)
        turtle.left(45)

    turtle.end_fill()
    turtle.exitonclick()

while (figura == "hexagono"):
    for x in range(6):
        turtle.forward(100)
        turtle.left(60)

    turtle.end_fill()
    turtle.exitonclick()