in python tutorial added that python cannot hide its attributes from other classes. some thing such as private data in C++ or java..But also i know that we can use _ or __ to set some variables as privated  one but it is not enogh. I think it is a weak if it is not any thing to do it.
Data encapsulation in Python is enforced by convention and peer review.  Surprisingly, having every attribute effectively be public hasn't caused a problem for the majority of Python programmers.
information hiding in python