如何在PyQt5中的Ui和类之间交换数据？

from PyQt5 import QtWidgets, uic
from PyQt5.QtCore import pyqtSlot

class MyMainWindow(QtWidgets.QMainWindow):
    def __init__(self):
        super(MyMainWindow, self).__init__()
        self.ui = Ui_MainWindow()
        self.ui.setupUi(self)
        
        # 连接信号和槽函数
        self.ui.pushButton.clicked.connect(self.on_button_clicked)

    @pyqtSlot()
    def on_button_clicked(self):
        # 读取界面中的数据
        input_text = self.ui.lineEdit.text()
        
        # 处理数据
        output_text = self.process_data(input_text)
        
        # 将处理后的数据显示在界面中
        self.ui.label.setText(output_text)

    def process_data(self, data):
        # 处理数据的逻辑
        processed_data = data.upper()  # 将输入的文本转换为大写
        
        return processed_data

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