Why does python not have a mechanism for data hiding?

[Sh4wn]

Hi,

first, python is one of my fav languages, and i'll definitely keep
developing with it. But, there's 1 one thing what I -really- miss:
data hiding. I know member vars are private when you prefix them with
2 underscores, but I hate prefixing my vars, I'd rather add a keyword
before it.

Python advertises himself as a full OOP language, but why does it miss
one of the basic principles of OOP? Will it ever be added to python?

Thanks in advance,
Lucas