Changing a shell's current directory with python

[Andy B.]

I've got a python utility that I want to change my shell's current
directory based on criteria it finds.  I've scoured google and the
python cookbook and can't seem to figure out if this is even possible.
 So far, all my attempts have changed the current python session only.
 Am I going to have to wrap this in a shell script?

% pwd
/var/tmp
% myutil.py
# do some stuff and cd to '/var/log'
% pwd
/var/log

Many thanks,

-A