Why is Ruby better than Python managing language? (is it?)

Hi there,
I'm starting to develop an application that is very demanding in
semantic capabilities, lots of relations between concepts... I heard
that ruby was better than any other programming language to manage
language... Is that true? Why?
(I still have to choose the language and Python with Django is the
other option I have, at least for the prototype. I won't be the main
programmer, but I have to start developing the idea...)

Thanks to all,

Valma