super and __class__ special case

[bjpop]

super and class are special cased in Python 3 classes.

See: http://docs.python.org/3/reference/datamodel.html#creating-the-class-object

"This class object is the one that will be referenced by the zero-argument form of super(). class is an implicit closure reference created by the compiler if any methods in a class body refer to either class or super. This allows the zero argument form of super() to correctly identify the class being defined based on lexical scoping, while the class or instance that was used to make the current call is identified based on the first argument passed to the method."

See also: http://www.python.org/dev/peps/pep-3135/#super-used-with-call-attributes

And in Python/symtable.c:

    /* Special-case super: it counts as a use of __class__ */
    if (e->v.Name.ctx == Load &&
        st->st_cur->ste_type == FunctionBlock &&
        !PyUnicode_CompareWithASCIIString(e->v.Name.id, "super")) {
        if (!GET_IDENTIFIER(__class__) ||
            !symtable_add_def(st, __class__, USE))
            return 0;
    }