from tkinter import Tk, scrolledtext, Menu, filedialog, END

# Root for main window
root = Tk(className = " New M@ Window")
textArea = scrolledtext.ScrolledText(root, width=80, height=100)
textArea.pack()

#
# FUNCTIONS
#

def openFile():
    file = filedialog.askopenfile(parent = root, mode = 'rb', title = "Select a file")

    if file != None:
        contents = file.read()
        textArea.insert('1.0', contents)
        file.close()

def saveFile():
    file = filedialog.asksaveasfile(mode = 'w')

    if file is not None:
        # Slice off the last character from get, as an extra return (enter) is added
        data = textArea.get('1.0', END + '-1c')
        file.write(data)
        file.close()

# Menu options
menu = Menu(root)
root.config(menu = menu)
fileMenu = Menu(menu)
menu.add_cascade(label = "File", menu = fileMenu)
fileMenu.add_command(label = "New")
fileMenu.add_command(label = "Open", command = openFile)
fileMenu.add_command(label = "Save")
fileMenu.add_command(label = "Print")
fileMenu.add_separator()
fileMenu.add_command(label = "Exit")

helpMenu = Menu(menu)
menu.add_cascade(label = "Help")
menu.add_cascade(label = "About")

# Keep window open
root.mainloop()