有没有办法在pyqt5或qt5中截取窗口的屏幕截图？

import sys
from PyQt5.QtWidgets import QApplication, QWidget
from PyQt5.QtGui import QPixmap

class MyWidget(QWidget):
    def __init__(self):
        super().__init__()
        self.initUI()

    def initUI(self):
        self.setGeometry(100, 100, 500, 500)
        self.setWindowTitle('Screen Capture Example')
        self.show()

    def paintEvent(self, event):
        # 获取屏幕
        screen = QApplication.primaryScreen()
        if screen is not None:
            # 截取当前窗口的屏幕截图
            screenshot = screen.grabWindow(self.winId())
            # 保存截图为文件
            screenshot.save('screenshot.png', 'png')

if __name__ == '__main__':
    app = QApplication(sys.argv)
    widget = MyWidget()
    sys.exit(app.exec_())