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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 postprocess_keyevent(self, event):

 """Process keypress event"""

        ShellBaseWidget.postprocess_keyevent(self, event)
        if QToolTip.isVisible():
            _event, _text, key, _ctrl, _shift = restore_keyevent(event)
            self.hide_tooltip_if_necessary(key)