Python GUI with PyQT5 : Insert Button - Part 3

Python GUI with PyQT5 Insert Button
Code :
from PyQt5.QtWidgets import QApplication,QWidget,QPushButton
from PyQt5.QtCore import pyqtSlot
import sys
class App(QWidget):
def __init__(self):
super().__init__()
def initUI(self):
button=QPushButton('Click Here',self)
if __name__=='__main__':
ex=App()