Python - Webkit - Zoom Text

#!/usr/bin/env python

import gtk, webkit

def go_but(widget):
    add = addressbar.get_text()
    if add.startswith("http://"):
            web.open(add)
    else:
            add = "http://" + add
            addressbar.set_text(add)
            web.open(add)

def zoom_in(widget):
     web.zoom_in()

def zoom_out(widget):
     web.zoom_out()

win = gtk.Window()
win.connect('destroy', lambda w: gtk.main_quit())

box1 = gtk.VBox()
win.add(box1)

box2 = gtk.HBox()
box1.pack_start(box2, False)


addressbar = gtk.Entry()
box2.pack_start(addressbar)

gobutton = gtk.Button("GO")
box2.pack_start(gobutton)
gobutton.connect('clicked', go_but)

zoom_in_button = gtk.Button("+")
box2.pack_start(zoom_in_button)
zoom_in_button.connect('clicked', zoom_in)

zoom_out_button = gtk.Button("-")
box2.pack_start(zoom_out_button)
zoom_out_button.connect('clicked', zoom_out)

scroller = gtk.ScrolledWindow()
box1.pack_start(scroller)

web = webkit.WebView()
scroller.add(web)

win.show_all()

gtk.main()