Python GTK。如何连续显示对话框？

import gi
gi.require_version('Gtk', '3.0')
from gi.repository import Gtk

def show_dialog(dialog):
    response = dialog.run()

    if response == Gtk.ResponseType.OK:
        print("OK button clicked")
    elif response == Gtk.ResponseType.CANCEL:
        print("Cancel button clicked")

    dialog.destroy()

def main():
    dialog1 = Gtk.MessageDialog(
        None,
        Gtk.DialogFlags.MODAL,
        Gtk.MessageType.INFO,
        Gtk.ButtonsType.OK_CANCEL,
        "This is dialog 1"
    )
    dialog1.set_title("Dialog 1")

    dialog2 = Gtk.MessageDialog(
        None,
        Gtk.DialogFlags.MODAL,
        Gtk.MessageType.INFO,
        Gtk.ButtonsType.OK_CANCEL,
        "This is dialog 2"
    )
    dialog2.set_title("Dialog 2")

    show_dialog(dialog1)
    show_dialog(dialog2)

if __name__ == "__main__":
    main()