class and private variables

Question

class Test1:
    def __init__( self ):
        self.__test = 1
    def getvalue( self ):
        return self.__test

class Test2( Test1 ):
    def __init__( self ):
        T         


        

Answer 1

In Python, private member __bar of class Foo will be automatically renamed to _Foo__bar, so the __test in Test1 is _Test1__test and that in Test2 is _Test2__test. The two members are actually different. This is by design, to "avoid name clashes of names with names defined by subclasses".

Use a single underscore _test if you want the subclass to see the variable while still want to keep it not part of the public interface.