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#!/usr/bin/python3
# -*- coding: utf-8 -*-
"""
ZetCode PyQt5 tutorial 
This program creates a skeleton of
a classic GUI application with a menubar,
toolbar, statusbar, and a central widget. 
Author: Jan Bodnar
Website: zetcode.com 
Last edited: August 2017
"""
import sys
from PyQt5.QtWidgets import QMainWindow, QTextEdit, QAction, QApplication
from PyQt5.QtGui import QIcon
class Example(QMainWindow):
    def __init__(self):
        super().__init__()
        self.initUI()
    def initUI(self):           
        textEdit = QTextEdit()
        self.setCentralWidget(textEdit)
        exitAct = QAction(QIcon('exit24.png'), 'Exit', self)
        exitAct.setShortcut('Ctrl+Q')
        exitAct.setStatusTip('Exit application')
        exitAct.triggered.connect(self.close)
        self.statusBar()
        menubar = self.menuBar()
        fileMenu = menubar.addMenu('&File')
        fileMenu.addAction(exitAct)
        toolbar = self.addToolBar('Exit')
        toolbar.addAction(exitAct)
        self.setGeometry(300, 300, 350, 250)
        self.setWindowTitle('Main window')  
        self.show()
if __name__ == '__main__':
    app = QApplication(sys.argv)
    ex = Example()
    sys.exit(app.exec_())

textEdit = QTextEdit()
self.setCentralWidget(textEdit)