Как вызвать свое диалоговое окно?

from PyQt5 import QtCore, QtGui, QtWidgets
 
 
class Ui_Form(object):
    def setupUi(self, Form):
        Form.setObjectName("Form")
        Form.resize(201, 152)
        self.verticalLayoutWidget = QtWidgets.QWidget(Form)
        self.verticalLayoutWidget.setGeometry(QtCore.QRect(0, 0, 201, 151))
        self.verticalLayoutWidget.setObjectName("verticalLayoutWidget")
        self.verticalLayout = QtWidgets.QVBoxLayout(self.verticalLayoutWidget)
        self.verticalLayout.setContentsMargins(0, 0, 0, 0)
        self.verticalLayout.setObjectName("verticalLayout")
        self.label = QtWidgets.QLabel(self.verticalLayoutWidget)
        self.label.setMaximumSize(QtCore.QSize(250, 50))
        self.label.setAlignment(QtCore.Qt.AlignCenter)
        self.label.setObjectName("label")
        self.verticalLayout.addWidget(self.label)
        self.label_2 = QtWidgets.QLabel(self.verticalLayoutWidget)
        self.label_2.setMaximumSize(QtCore.QSize(200, 30))
        self.label_2.setAlignment(QtCore.Qt.AlignCenter)
        self.label_2.setObjectName("label_2")
        self.verticalLayout.addWidget(self.label_2)
        self.lineEdit = QtWidgets.QLineEdit(self.verticalLayoutWidget)
        self.lineEdit.setMaximumSize(QtCore.QSize(200, 16777215))
        self.lineEdit.setObjectName("lineEdit")
        self.verticalLayout.addWidget(self.lineEdit)
        self.pushButton = QtWidgets.QPushButton(self.verticalLayoutWidget)
        self.pushButton.setMaximumSize(QtCore.QSize(200, 80))
        self.pushButton.setLayoutDirection(QtCore.Qt.LeftToRight)
        self.pushButton.setObjectName("pushButton")
        self.verticalLayout.addWidget(self.pushButton)
 
        self.retranslateUi(Form)
        QtCore.QMetaObject.connectSlotsByName(Form)
 
    def retranslateUi(self, Form):
        _translate = QtCore.QCoreApplication.translate
        Form.setWindowTitle(_translate("Form", "Form"))
        self.label.setText(_translate("Form", "Поздравляем с победой.\n Ваше время:"))
        self.label_2.setText(_translate("Form", "Введите ваше имя:"))
        self.pushButton.setText(_translate("Form", "Ok"))

import sys
from PyQt5.QtWidgets import *
from dialog import Ui_Dialog
 
class CustomDialog(QDialog):
    def __init__(self):
        super().__init__()
        self.ui = Ui_Dialog()
        self.ui.setupUi(self)
 
 
class App(QWidget):
 
    def __init__(self):
        super().__init__()
        self.title = 'PyQt5'
        self.left = 100
        self.top = 100
        self.width = 320
        self.height = 200
        self.initUI()
    
    def initUI(self):
        self.setWindowTitle(self.title)
        self.setGeometry(self.left, self.top, self.width, self.height)
        
        button = QPushButton('PyQt5 button', self)
        button.move(100,70)
        button.clicked.connect(self.on_click)
        
        self.show()
 
    def on_click(self):
        self.cust = CustomDialog()
        if self.cust.exec_():
            print('get')
        
 
if __name__ == '__main__':
    app = QApplication(sys.argv)
    ex = App()
    sys.exit(app.exec_())