[GR-11266] Revert enum.py patch

PullRequest: graalpython/160

Author: timfel

graalpython/lib-python/3/enum.py

@@ -340,9 +340,7 @@ def __members__(cls):
         is a read-only view of the internal mapping.
 
         """
-        # Truffle change
-        # return MappingProxyType(cls._member_map_)
-        return dict(cls._member_map_)
+        return MappingProxyType(cls._member_map_)
 
     def __repr__(cls):
         return "<enum %r>" % cls.__name__