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Attribute Names: Object Namespaces

Qualified attribute names refer to attributes of specific objects and obey the rules for modules and classes. For class and instance objects, the reference rules are augmented to include the inheritance search procedure:

Assignment (object.X = value)

Creates or alters the attribute name X in the namespace of the object being qualified, and none other. Inheritance-tree climbing happens only on attribute reference, not on attribute assignment.

Reference (object.X)

For class-based objects, searches for the attribute name X in object, then in all accessible classes above it, using the inheritance search procedure. For nonclass objects such as modules, fetches X from object directly.