如何在PyQt5中自定义QWizard的标题？

from PyQt5.QtWidgets import QApplication, QWizard, QWizardPage, QLabel, QVBoxLayout, QLineEdit

class MyWizard(QWizard):
    def __init__(self):
        super().__init__()
        self.setWindowTitle("自定义标题")
        
    def initializePage(self, pageId):
        if pageId == 0:
            self.setWizardStyle(QWizard.ModernStyle)
            self.setOption(QWizard.HaveCancelButton, True)
            self.setButtonText(QWizard.NextButton, "下一步")
            self.setPixmap(QWizard.WatermarkPixmap, QPixmap("watermark.png"))
            self.setSubTitle("这是副标题")
            self.setField("username", QLineEdit())
            self.registerField("username*", self.field("username"))
            
class Page1(QWizardPage):
    def __init__(self):
        super().__init__()
        layout = QVBoxLayout()
        label = QLabel("页面1")
        layout.addWidget(label)
        self.setLayout(layout)
        
class Page2(QWizardPage):
    def __init__(self):
        super().__init__()
        layout = QVBoxLayout()
        label = QLabel("页面2")
        layout.addWidget(label)
        self.setLayout(layout)

if __name__ == "__main__":
    app = QApplication([])
    wizard = MyWizard()
    wizard.addPage(Page1())
    wizard.addPage(Page2())
    wizard.show()
    app.exec_()