pyqt5 open window menubar

# Taken from https://www.learnpyqt.com/tutorials/creating-multiple-windows/
# and edited some few things

import sys
from PyQt5.QtWidgets import QApplication, QMainWindow, QWidget, QMenuBar, QAction


# New window to be created
class AnotherWindow(QWidget):
	def __init__(self):
    	super(AnotherWindow, self).__init__()
        """
        Works the same as a normal window (it's a window) so you
        can add things like `setWindowTitle` and such.
        """
        
        
# Main window
class MainWindow(QMainWindow):
	def __init__(self):
    	super(MainWindow, self).__init__()
        # Create action to be placed in the menu bar
        action = QAction('&New window'. self)
        action.triggered.connect(self.new_window)
        # Create menu bar
        menubar = QMenuBar(self)
        self.setMenuBar(menubar)
        # Add action to menu bar
        menubar.addAction(action)
        
    # Method for calling the other window
 	def new_window(self):
    	# Important! Add `self` to keep the window open until closed
    	self.another_window = AnotherWindow()
        self.another_window.show()
        

app = QApplication(sys.argv)
window = MainWindow()
window.show()
sys.exit(app.exec_())