newbie: prefix operator "**"

[Jeff Epler]

On Wed, Jan 21, 2004 at 10:33:49AM -0500, Christian Jauvin wrote:
> Hello,
> 
> I am playing with some classes in the Tkinter module
> to learn some GUI basics.

Take a look at the Tutorial, section 4.7.2.  The ** prefix for an
argument means that it accepts arbitrary keyword arguments.
http://python.org/doc/tut/node6.html#SECTION006720000000000000000

Example:

def f(**kw):
    print kw

>>> f(a=1, b=2)
{'a': 1, 'b': 2}

Tkinter uses this to pass the keyword arguments along to the next level,
eventually to the Tk command to create or configure a widget.

Jeff