cgi parser question ?

[Geirgat Jonas]

Hello,
maybe this isn't the right place to ask this question I know....
I have written a basic HTTP server in python now I would like it 
to have python CGI support only I haven't found how CGI works
is it like this a user requests a page you just parse it "python page.py"
and send to output to the user ?

any help, links would also help on this subject
regards Jonas