Python 3 Tkinter base window

Here is my Python 3 Tkinter base window code. It create a root window, puts a menubar with a quit option on it, adds a status bar and maximises the window. The code is meant to be self explanatory, so don't search for comments.

Syntax highlighted version here.

#! /usr/bin/env python3

from tkinter import Tk, Frame, Canvas, Menu, Label, SUNKEN, BOTTOM, W, X

class root_win(Tk):
    def __init__(self):
        Tk.__init__(self)
       
    def run(self):
        self.build_window()
        self.mainloop()
       
    def build_window(self):
        self.title('My prototype window')

        self.build_menu()
        self.build_statusbar()
        self.resize()

    def build_menu(self):
        self.menu = Menu()
        self.config(menu = self.menu)
       
        self.m_file = Menu(self.menu)
        self.m_file.add_command(
             label='Quit', command = self.destroy)
        self.menu.add_cascade(label='File', menu = self.m_file)
           
    def build_statusbar(self):
        self.statusbar = Label(borderwidth=1, relief=SUNKEN, anchor=W)
        self.statusbar.config( text = 'Started..')
        self.statusbar.pack(fill=X, side=BOTTOM)
       
    def resize(self):
        w, h = self.winfo_screenwidth(), self.winfo_screenheight()
        self.geometry("%dx%d+0+0" % (w, h))

gui = root_win()
gui.run()