从QMainWindow geometry()获取错误的位置

from PyQt5.QtWidgets import QMainWindow, QWidget, QApplication
from PyQt5.QtCore import QRect

class MyMainWindow(QMainWindow):
    def __init__(self):
        super().__init__()
        self.setWindowTitle("My Main Window")
        self.setGeometry(100, 100, 500, 500)

        central_widget = QWidget(self)
        self.setCentralWidget(central_widget)

        central_widget.setGeometry(50, 50, 400, 400)

    def get_content_geometry(self):
        central_widget = self.centralWidget()
        content_geometry = central_widget.geometry()
        return content_geometry

if __name__ == "__main__":
    app = QApplication([])
    window = MyMainWindow()
    window.show()

    content_geometry = window.get_content_geometry()
    print("Content Geometry:", content_geometry)

    app.exec_()