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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 keyPressEvent(self, ev):
 """Check the event. Return True if processed and False otherwise """

        if ev.key() in (Qt.Key_Shift, Qt.Key_Control,
                        Qt.Key_Meta, Qt.Key_Alt,
                        Qt.Key_AltGr, Qt.Key_CapsLock,
                        Qt.Key_NumLock, Qt.Key_ScrollLock):
            return False  # ignore modifier pressing. Will process key pressing later

        self._processingKeyPress = True
        try:
            ret = self._mode.keyPressEvent(ev)
        finally:
            self._processingKeyPress = False
        return ret