Как открыть второе окно в PyQt5?

Question

python_noob_80lv @python_noob_80lv

Python
PyQt

Как открыть второе окно в PyQt5?

У меня есть два дизайна окна

start:

# -*- coding: utf-8 -*-

# Form implementation generated from reading ui file '1-int.ui'
#
# Created by: PyQt5 UI code generator 5.13.0
#
# WARNING! All changes made in this file will be lost!


from PyQt5 import QtCore, QtGui, QtWidgets


class Ui_Start(object):
    def setupUi(self, Start):
        Start.setObjectName("Ui_Start")
        Start.resize(443, 293)
        Start.setStyleSheet("QPushButton:hover {backgroun-color: red}    \n"
"QPushButton:pressed {backgroun-color: blue\n"
"}\n"
"QPushButton{\n"
"    font: 45pt \"Molot\";\n"
"    backgroun-color: white;\n"
"    width: 75px ;\n"
"    height: 50px;\n"
"    font-size: 45px;\n"
"    font-weight: bold;\n"
"    bolder: none;\n"
"    text-align: center\n"
"}\n"
"\n"
"")
        self.lineEdit = QtWidgets.QLineEdit(Start)
        self.lineEdit.setGeometry(QtCore.QRect(50, 80, 321, 51))
        self.lineEdit.setStyleSheet("")
        self.lineEdit.setText("")
        self.lineEdit.setObjectName("lineEdit")
        self.textEdit = QtWidgets.QTextEdit(Start)
        self.textEdit.setGeometry(QtCore.QRect(10, 30, 421, 41))
        self.textEdit.setObjectName("textEdit")
        self.pushButton_2 = QtWidgets.QPushButton(Start)
        self.pushButton_2.setGeometry(QtCore.QRect(150, 210, 141, 58))
        self.pushButton_2.setStyleSheet("font: 16pt \"Molot\";")
        self.pushButton_2.setObjectName("pushButton_2")
        self.pushButton = QtWidgets.QPushButton(Start)
        self.pushButton.setGeometry(QtCore.QRect(50, 140, 321, 58))
        self.pushButton.setObjectName("pushButton")

        self.retranslateUi(Start)
        QtCore.QMetaObject.connectSlotsByName(Start)

    def retranslateUi(self, v):
        _translate = QtCore.QCoreApplication.translate
        Start.setWindowTitle(_translate("Start", "Start"))
        self.textEdit.setHtml(_translate("Start", "<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.0//EN\" \"http://www.w3.org/TR/REC-html40/strict.dtd\">\n"
"<html><head><meta name=\"qrichtext\" content=\"1\" /><style type=\"text/css\">\n"
"p, li { white-space: pre-wrap; }\n"
"</style></head><body style=\" font-family:\'MS Shell Dlg 2\'; font-size:8.25pt; font-weight:400; font-style:normal;\">\n"
"<p align=\"center\" style=\" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px;\"><span style=\" font-size:16pt;\">введите номер и букву класса класса :</span></p></body></html>"))
        self.pushButton_2.setText(_translate("Start", "инструкция"))
        self.pushButton.setText(_translate("Start", "1"))


if __name__ == "__main__":
    import sys
    app = QtWidgets.QApplication(sys.argv)
    Start = QtWidgets.QWidget()
    ui = Ui_Start()
    ui.setupUi(Start)
    Start.show()
    sys.exit(app.exec_())

inst:

from PyQt5 import QtCore, QtGui, QtWidgets


class Ui_Inst(object):
    def setupUi(self, Inst):
        Inst.setObjectName("Ui_Inst")
        Inst.resize(1111, 883)
        self.textEdit = QtWidgets.QTextEdit(v)
        self.textEdit.setGeometry(QtCore.QRect(0, 10, 1111, 41))
        self.textEdit.setObjectName("textEdit")
        self.text_inctru = QtWidgets.QTextEdit(Inst)
        self.text_inctru.setGeometry(QtCore.QRect(20, 60, 1071, 811))
        self.text_inctru.setObjectName("text_inctru")

        self.retranslateUi(Inst)
        QtCore.QMetaObject.connectSlotsByName(v)

    def retranslateUi(self, Inst):
        _translate = QtCore.QCoreApplication.translate
        Inst.setWindowTitle(_translate("Inst", "Inst"))
        self.textEdit.setHtml(_translate("Inst", "<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.0//EN\" \"http://www.w3.org/TR/REC-html40/strict.dtd\">\n"
"<html><head><meta name=\"qrichtext\" content=\"1\" /><style type=\"text/css\">\n"
"p, li { white-space: pre-wrap; }\n"
"</style></head><body style=\" font-family:\'MS Shell Dlg 2\'; font-size:8.25pt; font-weight:400; font-style:normal;\">\n"
"<p align=\"center\" style=\" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px;\"><span style=\" font-size:22pt;\">Инструкция</span></p></body></html>"))

Как открыть второе окно, нажав кнопку.