When do those groups show up because without them we would not have art here on the Internet or even here. Always there underneath providing the framework of what will be in the space taken or given.
try:
import tkinter
except ImportError: # python 2
import Tkinter as tkinter

import os
mainWindow = tkinter.Tk()

mainWindow.title("Grid Demo")
mainWindow.geometry('640x480-8-200')

label = tkinter.Label(mainWindow, text="Tkinter Grid Demo")
label.grid(row=0, column=0, columnspan=3)

mainWindow.columnconfigure(0, weight=1)
mainWindow.columnconfigure(1, weight=1)
mainWindow.columnconfigure(2, weight=3)
mainWindow.columnconfigure(3, weight=3)
mainWindow.columnconfigure(4, weight=3)
mainWindow.rowconfigure(0, weight=1)
mainWindow.rowconfigure(1, weight=10)
mainWindow.rowconfigure(2, weight=1)
mainWindow.rowconfigure(3, weight=3)
mainWindow.rowconfigure(4, weight=3)

fileList = tkinter.Listbox(mainWindow)
fileList.grid(row=1, column=0, sticky="nsew", rowspan=2)
fileList.config(border=2, relief="sunken")

for zone in os.listdir('/Windows/System32'):
fileList.insert(tkinter.END, zone)

mainWindow.mainloop()
image.png