Python regex get URL from string

I'm using regular expressions to get a URL from a string

Here is my code:

import re

class ProcessWebsite(object):

    def __init__(self, *args, **kwargs):
        print "Test"

    def set_orden(self, command):
        self.command = command
        return self.getURL()

    def getURL(self):
        regex = re.compile("([0-9A-Za-z]{2,}\.[0-9A-Za-z]{2,3}\.[0-9A-Za-z]{2,3}|[0-9A-Za-z]{2,}\.[0-9A-Za-z]{2,3})$")
        return regex.findall(str(self.command))

I call the method "getURL" from here:

# -*- coding: utf-8 -*-
import Tkinter as tk
import tkFont
from Tkinter import StringVar
from Tkinter import Label
from processor.processwebsite import ProcessWebsite



def changeText(newText):
    var.set(newText)

def on_return_release(event):
    pr = ProcessWebsite()
    changeText(pr.set_orden(text.get("1.0", "end")))



app = tk.Tk()

var = StringVar()
label = Label(app, textvariable=var) 
font = tkFont.Font(family='Helvetica', size=36, weight='bold')
label.pack()

text = tk.Text(app, width=50, font=font)
text.config(width=35, height=2)
text.pack()
text.bind("<KeyRelease-Return>", on_return_release)

app.mainloop()

This returns me "None", but if I change this line of the method "getURL" then it works

def getURL(self):
        regex = re.compile("([0-9A-Za-z]{2,}\.[0-9A-Za-z]{2,3}\.[0-9A-Za-z]{2,3}|[0-9A-Za-z]{2,}\.[0-9A-Za-z]{2,3})$")
        return regex.findall("Test with google.com")

Does anyone know what could be happening?

Thanks