Bypass a web login when userid and password are known.

[CDW]

I would like to know if it is possible to write a python cgi program
that, when executed, can login to a website that uses cookies and
requires a userid and password, then presents me with the first
document past the login screen  just as though I had entered the login
information manually (In other words, bypass the login if I know the
userid and password). This is part of portal project that I have been
doing some research on and it would go a long way toward helping us to
establish a single sign-on portal.