Newbie question on wxNotebook

[Klaus Oberpichler]

Can anyone please tell me why my notebook is not visible?
Thanks in advance!

Klaus

from wxPython.wx import *

#---------------------------------------------------------------------------

## Create a new frame class, derived from the wxPython Frame.
class MyFrame(wxFrame):

    def __init__(self, parent, id, title):
        # First, call the base class' __init__ method to create the frame
        wxFrame.__init__(self, parent, id, title,
                         wxPoint(100, 100), wxSize(400, 400))

        # Create a menu
        self.mnu = wxMenuBar()

        menu1 = wxMenu()
        menu1.Append(wxNewId(), "&Mercury", "This the text in the
Statusbar")
        menu1.Append(wxNewId(), "&Venus", "")
        menu1.Append(wxNewId(), "&Earth", "You may select Earth too")
        menu1.AppendSeparator()
        menu1.Append(wxNewId(), "&Close", "Close this frame")

        self.mnu.Append(menu1,"&Datei")
        self.SetMenuBar(self.mnu)

        # Create a toolbar
        self.tb = self.CreateToolBar()

        # Create a statusbar
        self.sb = self.CreateStatusBar()

        # Create notebook
        nb = wxNotebook(self, -1)
        panel1 = wxPanel(nb, -1)
        panel2 = wxPanel(nb, -1)
        nb.AddPage(panel1, "Panel 1")
        nb.AddPage(panel2, "Panel 2")


        # Associate some events with methods of this class
        EVT_SIZE(self, self.OnSize)
        EVT_MOVE(self, self.OnMove)



    # This method is called automatically when the CLOSE event is
    # sent to this window
    def OnCloseWindow(self, event):
        # tell the window to kill itself
        self.Destroy()


    # This method is called by the System when the window is resized,
    # because of the association above.
    def OnSize(self, event):
        size = event.GetSize()
        print "size:", size.width, size.height

    # This method is called by the System when the window is moved,
    # because of the association above.
    def OnMove(self, event):
        pos = event.GetPosition()
        print "pos:", pos.x, pos.y


#class TestNB(wxNotebook):
#    def __init__(self, parent, id):
#        wxNotebook.__init__(self, parent, id, style=
#                            #wxNB_TOP
#                            wxNB_BOTTOM
#                            #wxNB_LEFT
#                            #wxNB_RIGHT
#                            )

#---------------------------------------------------------------------------

# Every wxWindows application must have a class derived from wxApp
class MyApp(wxApp):

    # wxWindows calls this method to initialize the application
    def OnInit(self):

        # Create an instance of our customized Frame class
        frame = MyFrame(NULL, -1, "This is a test")
        frame.Show(true)

        # Tell wxWindows that this is our main window
        self.SetTopWindow(frame)

        # Return a success flag
        return true

#---------------------------------------------------------------------------

app = MyApp(0)     # Create an instance of the application class
app.MainLoop()     # Tell it to start processing events

#---------------------------------------------------------------------------
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