using vim as a python class/module/function etc.. browser

[Chris Jones]

I'm trying to make sense of a python program and was wondering if vim 
has any python-oriented functionalities (apart from syntax highlighting) 
that would make it somewhat easier to browse the source code.

What I had in mind is something that would let me use CTRL+] to 
automatically display whatever object is under the cursor (a bit like 
ctags for code written in C..)

I have read somewhere about something called 'ptags' but could not find 
it in debian - and I'm not 100% sure it's really a python equivalent of 
ctags.

I'm not too keen on using a gui IDE and would much prefer to stick with 
vim if at all possible.

Any pointers or tips from python/vim folks welcome.

CJ