Currently we don't specialize loading of enum attributes.
class Color(Enum): RED = "Red" Color.RED # This load is not specialized
We can take advantage of the fact that type(Color.RED) == Color when specializing.
Since we check the version number of Color in LOAD_ATTR_CLASS, we are implicitly checking the version of type(Color.RED).
If Color.RED is not a descriptor when specialized, it will not be a descriptor when executed.
Therefore, we can specialize it in the same way as immutable, non-descriptor class attributes using LOAD_ATTR_CLASS.