Why doesn't the pyqt5 button fire?

Question

PyQt

the function is attached to the button, but it doesn't fire when clicked, it should change the button's name when clicked

from PyQt5 import QtCore, QtGui, QtWidgets
from PyQt5.Qt import *
class Thread(QThread):
    signal = pyqtSignal(str)

    def __init__(self):
        super().__init__()
        self.flag = True


    def run(self):
        while self.flag:
            print('b')
            self.msleep(2000)

    def stop(self):
        self.flag = False
class Ui_MainWindow(object):
    def setupUi(self, MainWindow):
        MainWindow.setObjectName("MainWindow")
        MainWindow.resize(480, 640)
        MainWindow.setMinimumSize(QtCore.QSize(480, 640))
        MainWindow.setMaximumSize(QtCore.QSize(480, 640))
        self.centralwidget = QtWidgets.QWidget(MainWindow)
        self.centralwidget.setObjectName("centralwidget")
        self.btn_start = QtWidgets.QPushButton(self.centralwidget)
        self.btn_start.setGeometry(QtCore.QRect(80, 450, 311, 111))
        font = QtGui.QFont()
        font.setFamily("Arial")
        font.setPointSize(15)
        self.btn_start.setFont(font)
        self.btn_start.setStyleSheet("color: rgb(0, 0, 0);\n"
"")
        self.btn_start.setObjectName("btn_start")
        self.label = QtWidgets.QLabel(self.centralwidget)
        self.label.setGeometry(QtCore.QRect(0, 0, 481, 391))
        self.label.setText("")
        self.label.setPixmap(QtGui.QPixmap("upload-004-pic685-685x390-91733.jpg"))
        self.label.setObjectName("label")
        MainWindow.setCentralWidget(self.centralwidget)
        self.statusbar = QtWidgets.QStatusBar(MainWindow)
        self.statusbar.setObjectName("statusbar")
        MainWindow.setStatusBar(self.statusbar)

        self.retranslateUi(MainWindow)
        QtCore.QMetaObject.connectSlotsByName(MainWindow)
        self.thread = Thread()


    def retranslateUi(self, MainWindow):
        _translate = QtCore.QCoreApplication.translate
        MainWindow.setWindowTitle(_translate("MainWindow", "АнтиАфк"))
        self.btn_start.setText(_translate("MainWindow", "Запуск"))

    def add_functionts(self):
        self.btn_start.clicked.connect(self.OnClicked)
    def OnClicked(self):
        _translate = QtCore.QCoreApplication.translate
        if self.btn_start.text()=='Запуск':
            self.thread.flag = True
            self.thread.start()
            print('Работает')
            self.btn_start.setText("Стоп")
        else:
            self.thread.flag = False
            self.btn_start.setText("Запуск")
            print('Все')

UPD: Sorry for posting so much code, just xs where exactly is the error

Answer 1

You forgot to add the add_functionts function to retranslateUi()
Correct:

spoiler

def retranslateUi(self, MainWindow):
    _translate = QtCore.QCoreApplication.translate
    MainWindow.setWindowTitle(_translate("MainWindow", "АнтиАфк"))
    self.btn_start.setText(_translate("MainWindow", "Запуск"))
    add_functionts()