trying to use code_swarm but Im having some python scripting problems with perforce on osx

Question

I am having issues running this:

link-mbp:codeswarm-0.1 benb$ python convert_logs/convert_logs.py -perforce-path
Traceback (most recent call last):
File “convert_logs/convert_logs.py”, line 408, in
main()
File “convert_logs/convert_logs.py”, line 350, in main
files = run_marshal(’p4 -G describe -s “‘ + changelist['change'] + ‘”‘)
KeyError: ‘change’
link-mbp:codeswarm-0.1 benb$

I am trying to use code_swarm from this link http://blog.perforce.com/blog/?p=780&cpage=1#comment-965 to visualize my codebase changes.

if I run p4 changes everything shows correct but the code in this python script doesnt seem to process correctly...

if I run p4 describe on a a changelist number it correctly reports

ideas?