def METHOD_NAME(snippetcompiler):
    snippetcompiler.setup_for_snippet(
        """
    entity A:
        bool at = true
    end
    implement A using std::none
    entity B extends A:
        bool at = false
    end
    implement B using std::none
    a = A()
    b = B()
    """
    )
    (_, scopes) = compiler.do_compile()
    root = scopes.get_child("__config__")
    a = root.lookup("a")
    assert a.get_value().get_attribute("at").get_value() is True
    b = root.lookup("b")
    assert b.get_value().get_attribute("at").get_value() is False