Tkinter w.pack()?

[W. eWatson]

Where in the world is a description of pack() for Tkinter widgets? Is it 
some sort of general method for all widgets? I'm looking in a few docs that 
use it without ever saying where it is described. For one, 
<http://effbot.org/tkinterbook/label.htm>. In the NM Tech pdf on Tkinter, 
it's not found anywhere. I see Universal methods for widgets, but no mention 
of pack(). package, packed, but no pack.

While I'm at it, what is w in the result of w = Label(parent, image=photo)? 
Just a widget pointer, address?
-- 
                                W. eWatson

              (121.015 Deg. W, 39.262 Deg. N) GMT-8 hr std. time)
               Obz Site:  39° 15' 7" N, 121° 2' 32" W, 2700 feet

                     Web Page: <www.speckledwithstars.net/>