如何检查以下QMessageBox中的哪个按钮被单击？ button == QMessageBox.Ok无法正常工作。

class WarningWindow(QMessageBox):

    nextWindowSignal = pyqtSignal()

    def __init__(self):
        super().__init__()

        self.setWindowTitle('A title')
        self.setText("Generic text")
        self.setStandardButtons(QMessageBox.Ok | QMessageBox.Cancel)
        self.buttonClicked.connect(self.nextWindow)

    def nextWindow(self,button):
        if button == QMessageBox.Ok:
            print('ok')
        elif button == QMessageBox.Cancel:
            print('cancel')
        else:
            print('other)

        self.nextWindowSignal.emit()