This is actually the same thing as regular Python scoping rules; there's not even any fancy OOP logic behind it. Here's the same thing, but using global scope and functions instead of classes and inheritance.

     >>> x = 1
     >>> def a():
    ...:     print(x)
    ...:
     >>> def b():
    ...:     x = 2
    ...:     print(x)
    ...:
     >>> def c():
    ...:     print(x)
    ...:
     >>> a(), b(), c()
    1
    2
    1
     >>> x = 3
     >>> a(), b(), c()
    3
    2
    3

I think there is an argument to be made that classes are special and "reaching upwards" into the superclass scope should not occur - a unique copy should be made - but I also think that Python's way of doing it makes enough sense that it is not confusing. The Python devs are at least consistent about having their own way of doing things.