GTK Text input set focus

#!/usr/bin/env python

import pygtk
pygtk.require('2.0')
import gtk

class HelloWorld:

    def hello(self, widget, data=None):
        print "Hello World"

    def delete_event(self, widget, event, data=None):
        print "delete event occurred"

        return False

    def destroy(self, widget, data=None):
        print "destroy signal occurred"
        gtk.main_quit()

    def __init__(self):
        self.window = gtk.Window(gtk.WINDOW_TOPLEVEL)
        self.window.connect("delete_event", self.delete_event)
        self.window.connect("destroy", self.destroy)
        self.window.set_border_width(10)

        self.box = gtk.VBox(False, 0)
        self.window.add(self.box)

        self.button = gtk.Button("Close Window")
        self.button.connect("clicked", self.hello, None)
        self.button.connect_object("clicked", gtk.Widget.destroy, self.window)
        self.box.pack_start(self.button)


        self.entry1=gtk.Entry()
        self.box.pack_start(self.entry1)

        self.entry2=gtk.Entry()
        self.box.pack_start(self.entry2)

        self.entry3=gtk.Entry()
        self.box.pack_start(self.entry3)

        self.entry4=gtk.Entry()
        self.box.pack_start(self.entry4)

        self.window.show_all()

        self.entry2.grab_focus()
    def main(self):
        gtk.main()

if __name__ == "__main__":
    hello = HelloWorld()
    hello.main()