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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 event(self, event):

 """Qt Override.
 
 Filter tab keys and process double tab keys.
 """

        if (event.type() == QEvent.KeyPress) and (event.key() == Qt.Key_Tab):
            self.sig_tab_pressed.emit(True)
            self.numpress += 1
            if self.numpress == 1:
                self.presstimer = QTimer.singleShot(400, self.handle_keypress)
            return True
        return QComboBox.event(self, event)