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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def register_on_guest_keyboard(self, callback):
 """Set the callback function to consume on guest keyboard events Callback receives a IGuestKeyboardEvent object. Example: def callback(event):
 print(event.scancodes) """

        return self.event_source.register_callback(callback,
                                                   library.VBoxEventType.on_guest_keyboard)