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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 force_screen_saver(self, mode, onerror = None):
 """If mode is X.ScreenSaverActive the screen saver is activated. If it is X.ScreenSaverReset, the screen saver is deactivated as if device input had been received."""

        request.ForceScreenSaver(display = self.display,
                                 onerror = onerror,
                                 mode = mode)