Python - How to make a QR code image with Python

This script use Tkinter, Image and pyqrcode to make an image of the text entered in the text field.

from Tkinter import *
import Image
import pyqrcode

''' Functions '''
def makeQRCode():
    qr_data = txt_Input.get()
    url = pyqrcode.create(qr_data)
    url.png('url.png', scale = 8)
    img ='url.png')

    print (qr_data)

def clearInputField():
    txt_Input.delete(0, 'end')

''' This will make the main window '''
window = Tk()
window.title("QR Code generator")

''' This will place labels, entries and buttons '''
lbl_Header = Label(window, text="Enter source text to make QR code from")
lbl_Header.grid(column=0, row=0)

txt_Input = Entry(window, width=20)
txt_Input.grid(column=0, row=1)

btn_MakeQRCode = Button(window, text="Make QR code", command=makeQRCode)
btn_MakeQRCode.grid(column=0, row=2)

btn_Clear = Button(window, text="Clear", command=clearInputField)
btn_Clear.grid(column=0, row=3)

btn_Quit = Button(window, text="Quit", command=window.quit)
btn_Quit.grid(column=0, row=4)

''' Run the mainloop '''