from Tkinter import * class WindowList:     def __init__(self):        self.dict = {}        self.callbacks = []     def add(self, window):        window.after_idle(self.call_callbacks)        self.dict[str(window)] = window     def delete(self, window):        try:            del self.dict[str(window)]        except KeyError:            # Sometimes, destroy() is called twice            pass        self.call_callbacks()     def add_windows_to_menu(self,  menu):        list = []        for key in self.dict.keys():            window = self.dict[key]            try:                title = window.get_title()            except TclError:                continue            list.append((title, window))        list.sort()        for title, window in list:            menu.add_command(label=title, command=window.wakeup)     def register_callback(self, callback):        self.callbacks.append(callback)     def unregister_callback(self, callback):        try:            self.callbacks.remove(callback)        except ValueError:            pass     def call_callbacks(self):        for callback in self.callbacks:            try:                callback()            except:                print "warning: callback failed in WindowList", \                      sys.exc_type, ":", sys.exc_value registry = WindowList() add_windows_to_menu = registry.add_windows_to_menuregister_callback = registry.register_callbackunregister_callback = registry.unregister_callback  class ListedToplevel(Toplevel):     def __init__(self, master, **kw):        Toplevel.__init__(self, master, kw)        registry.add(self)        self.focused_widget = self     def destroy(self):        registry.delete(self)        Toplevel.destroy(self)        # If this is Idle's last window then quit the mainloop        # (Needed for clean exit on Windows 98)        if not registry.dict:            self.quit()     def update_windowlist_registry(self, window):        registry.call_callbacks()     def get_title(self):        # Subclass can override        return self.wm_title()     def wakeup(self):        try:            if self.wm_state() == "iconic":                self.wm_withdraw()                self.wm_deiconify()            self.tkraise()            self.focused_widget.focus_set()        except TclError:            # This can happen when the window menu was torn off.            # Simply ignore it.            pass