OO programing in vizard?

[renama]

Here is the code of the class (same with the previous attachement)

class MusicOnOff:
       def __init__(self,musicObj):
             self. Obj = musicObj
             self.musicIcon = viz.addTexQuad()
             self.musicIcon.texture(viz.add((‘musicOff.png')))
             self.musicOn = True
             viz.callback( viz.MOUSEDOWN_EVENT, self.onMouseDown )
       def onMouseDown(self, button):
             if button == viz.MOUSEBUTTON_LEFT:
                   object = viz.pick()
                   if object.valid() == False: return
                   if object == self.musicIcon:
                          if self.musicOn == True:
                                 self.musicOn = False
                                 self.musicIcon.texture(viz.add((‘musicOn.png')))
                                 self.Obj.pause()				
                          else:
                                 self.musicOn = True
                                 self.musicIcon.texture(viz.add((‘musicOff.png')))
                                 self.Obj.play()