Python Data-hiding

Question

In quiz 2/3 of Data-hiding section of Python course among the answers you can choose you have:
- To mark it as private
- To prevent it being called by external code
but from a point of view of concept they're identical. When you mark a variable as private is seen only inside a class AND is inaccessible from outer code. isn't it?

Answer 1

Ok. Just to clarify.
From a concept point of view is like I write before. A private variable is invisible outside a class.
In python "usually" use an underscore ( _ ) to consider a variable as "private".
But it's still a public variable.
But if you put two underscores ( __ ) Python as safety measure mark it as "private" to avoid erroneous overriding of methods/variables (but still reachable via _class__variable format)