I had a question regarding changes in subclassingEnum in 3.11. As of 3.11, if enum class has a mixin parent apart fromEnum which has defined__init__ or__new__,member._value_ is set to be another instance of the mixin class
unless user defines__new__ in the enum class and set_value_. However user naturally expects_value_ to be the value assigned to the member in class definition. In the example below

classmixin:def__init__(self):passclassCustomEnum(mixin,Enum):MEMBER="member"

CustomEnum.MEMBER is an instance of mixin andCustomEnum.MEMBER.value is another instance of it (with different id), while it was expected thatCustomEnum.MEMBER.value would be"member". What has been the rationale for this change?

By the way, this change is not noted in python docs enumeration page.

Linked PRs

• gh-103479: [Enum] require __new__ to be considered a data type #103495
• [3.11] gh-103479: [Enum] require __new__ to be considered a data type (GH-103495) #103514