PyQt5 сменить вкладку по нажатию кнопки?

Question

[hohopro35]

from PyQt5 import QtCore, QtGui, QtWidgets


class Ui_MainWindow(object):
    def setupUi(self, MainWindow):
        MainWindow.setObjectName("MainWindow")
        MainWindow.resize(600, 462)
        self.centralwidget = QtWidgets.QWidget(MainWindow)
        self.centralwidget.setObjectName("centralwidget")
        self.tabWidget = QtWidgets.QTabWidget(self.centralwidget)
        self.tabWidget.setGeometry(QtCore.QRect(20, 10, 341, 241))
        self.tabWidget.setObjectName("tabWidget")
        self.tab = QtWidgets.QWidget()
        self.tab.setObjectName("tab")
        self.calendarWidget = QtWidgets.QCalendarWidget(self.tab)
        self.calendarWidget.setGeometry(QtCore.QRect(10, 0, 241, 131))
        self.calendarWidget.setObjectName("calendarWidget")
        self.pushButton = QtWidgets.QPushButton(self.tab)
        self.pushButton.setGeometry(QtCore.QRect(140, 150, 111, 41))
        self.pushButton.setObjectName("pushButton")
        self.tabWidget.addTab(self.tab, "")
        self.tab_2 = QtWidgets.QWidget()
        self.tab_2.setObjectName("tab_2")
        self.dateEdit = QtWidgets.QDateEdit(self.tab_2)
        self.dateEdit.setGeometry(QtCore.QRect(80, 60, 110, 22))
        self.dateEdit.setObjectName("dateEdit")
        self.pushButton_2 = QtWidgets.QPushButton(self.tab_2)
        self.pushButton_2.setGeometry(QtCore.QRect(70, 140, 91, 31))
        self.pushButton_2.setObjectName("pushButton_2")
        self.tabWidget.addTab(self.tab_2, "")
        MainWindow.setCentralWidget(self.centralwidget)

        self.retranslateUi(MainWindow)
        self.tabWidget.setCurrentIndex(1)
        QtCore.QMetaObject.connectSlotsByName(MainWindow)

    def retranslateUi(self, MainWindow):
        _translate = QtCore.QCoreApplication.translate
        MainWindow.setWindowTitle(_translate("MainWindow", "MainWindow"))
        self.pushButton.setText(_translate("MainWindow", "Кнопка 1"))
        self.tabWidget.setTabText(self.tabWidget.indexOf(self.tab), _translate("MainWindow", "Tab 1"))
        self.pushButton_2.setText(_translate("MainWindow", "Кнопка 2"))
        self.tabWidget.setTabText(self.tabWidget.indexOf(self.tab_2), _translate("MainWindow", "Tab 2"))


if __name__ == "__main__":
    import sys
    app = QtWidgets.QApplication(sys.argv)
    MainWindow = QtWidgets.QMainWindow()
    ui = Ui_MainWindow()
    ui.setupUi(MainWindow)
    MainWindow.show()
    sys.exit(app.exec_())

Как я могу сделать так, чтобы при нажатии на кнопку 1, открывалась вкладка 2, а при нажатии кнопки 2, активировалась первая вкладка?