Passing a String to a Python CGI Script

[DeepBleu]

When one is using an HTML form via a web broswer, the user submits the form
contents and these are passed to a CGI Python script on the web server.
I need to write a client script that connects to a web site, runs a Python
CGI script on the web server AND passes a string to the CGI Python script
that the Python CGI script can store/manipulate/evalute etc....
I know how to connect to the web site and run the CGI Python script using a
client Python script with the urllib module.  But how do I submit/send a
string via this client Python script to the web server on behalf of the CGI
Python script?  Can someone give me a clue or a hint on how to do that?  Do
I write the string to the web server?  If so, how would the CGI Python
script know about it, read it, and store it?
Thanks,
DeepBleu