如何为小工具创建不同的字体大小，并允许它们随PySide2中的字体对话框进行缩放？

from PySide2.QtWidgets import QApplication, QWidget, QPushButton, QFontDialog
from PySide2.QtGui import QFont, QFontMetrics

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

        self.initUI()

    def initUI(self):
        self.button = QPushButton('Hello World', self)
        self.button.clicked.connect(self.showFontDialog)

        self.setGeometry(300, 300, 300, 200)
        self.setWindowTitle('Font Scaling Example')
        self.show()

    def showFontDialog(self):
        font, ok = QFontDialog.getFont()
        if ok:
            self.button.setFont(font)
            self.scaleButtonFont()

    def scaleButtonFont(self):
        fontMetrics = QFontMetrics(self.button.font())
        textSize = fontMetrics.size(0, self.button.text())
        self.button.resize(textSize)

if __name__ == '__main__':
    app = QApplication([])
    widget = MyWidget()
    app.exec_()