效果如下图：

1 """ 2 This example shows an icon 3 in the titlebar of the window. 4  5 """ 6  7 import sys 8 from PyQt5.QtWidgets import QApplication, QWidget 9 from PyQt5.QtGui import QIcon10 11 12 class Example(QWidget):  # The Example class inherits from the QWidget class13 14     def __init__(self):15         super().__init__()  # The super() method returns the parent object of the Example class16 17         self.initUI()18 19     def initUI(self):20 21         # locates the window on the screen and sets it size22         self.setGeometry(300, 300, 300, 220)23 24         # set the title of the window25         self.setWindowTitle('Hello World')26 27         # sets the application icon28         # The QIcon receives the path to our icon29         self.setWindowIcon(QIcon('web.png'))30 31         self.show()32 33 34 if __name__ == '__main__':35 36     app = QApplication(sys.argv)37     ex = Example()38     sys.exit(app.exec_())

 

 

问题：如何将标题居中？