源代码：

# -*- coding: utf-8 -*-# Form implementation generated from reading ui file 'qt_mainwindow.ui'
#
# Created by: PyQt5 UI code generator 5.15.9
#
# WARNING: Any manual changes made to this file will be lost when pyuic5 is
# run again.  Do not edit this file unless you know what you are doing.from PyQt5 import QtCore, QtGui, QtWidgets
from PyQt5.QtCore import *
from PyQt5.QtGui import *
from PyQt5.QtWidgets import *
import sysclass Ui_MainWindow(object):def setupUi(self, MainWindow):MainWindow.setObjectName("MainWindow")MainWindow.resize(800, 600)self.centralwidget = QtWidgets.QWidget(MainWindow)self.centralwidget.setObjectName("centralwidget")self.tableView = QtWidgets.QTableView(self.centralwidget)self.tableView.setGeometry(QtCore.QRect(10, 10, 781, 521))self.tableView.setObjectName("tableView")MainWindow.setCentralWidget(self.centralwidget)self.menubar = QtWidgets.QMenuBar(MainWindow)self.menubar.setGeometry(QtCore.QRect(0, 0, 800, 26))self.menubar.setObjectName("menubar")self.menuMain = QtWidgets.QMenu(self.menubar)self.menuMain.setObjectName("menuMain")MainWindow.setMenuBar(self.menubar)self.statusbar = QtWidgets.QStatusBar(MainWindow)self.statusbar.setObjectName("statusbar")MainWindow.setStatusBar(self.statusbar)self.actionAdd_New_Wiindow = QtWidgets.QAction(MainWindow)self.actionAdd_New_Wiindow.setObjectName("actionAdd_New_Wiindow")self.menuMain.addAction(self.actionAdd_New_Wiindow)self.menubar.addAction(self.menuMain.menuAction())self.actionAdd_New_Wiindow.triggered.connect(self.showWidget)self.Dialog = QtWidgets.QDialog(self.centralwidget)self.Dialog.setObjectName("Dialog")self.Dialog.resize(400, 300)self.Dialog.setModal(True)#self.Dialog.setWindowModality(Qt.WindowModality)self.Dialog.hide()self.buttonBox = QtWidgets.QDialogButtonBox(self.Dialog)self.buttonBox.setGeometry(QtCore.QRect(30, 240, 341, 32))self.buttonBox.setOrientation(QtCore.Qt.Horizontal)self.buttonBox.setStandardButtons(QtWidgets.QDialogButtonBox.Cancel|QtWidgets.QDialogButtonBox.Ok)self.buttonBox.setObjectName("buttonBox")self.buttonBox.accepted.connect(self.accept) # type: ignoreself.buttonBox.rejected.connect(self.reject) # type: ignoreself.retranslateUi(MainWindow)QtCore.QMetaObject.connectSlotsByName(MainWindow)def retranslateUi(self, MainWindow):_translate = QtCore.QCoreApplication.translateMainWindow.setWindowTitle(_translate("MainWindow", "MainWindow"))self.menuMain.setTitle(_translate("MainWindow", "Main"))self.actionAdd_New_Wiindow.setText(_translate("MainWindow", "Show Dialog"))self.Dialog.setWindowTitle(_translate("Dialog", "Dialog"))def show(self, Form):Form.show()def showWidget(self):self.Dialog.show()def accept(self):self.Dialog.hide()def reject(self):self.Dialog.hide()if __name__ == "__main__":app = QApplication(sys.argv)Form=QtWidgets.QMainWindow()    main_win = Ui_MainWindow()    main_win.setupUi(Form)main_win.show(Form)sys.exit(app.exec())        

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