Having trouble writing an Enum with a custom __new__ method

[deanhystad]

From the docs you referenced:

Output:
When to use __new__() vs. __init__()
__new__() must be used whenever you want to customize the actual value of the Enum member. Any other modifications may go in either __new__() or __init__(), with __init__() being preferred.

In other words use __new__ when you want to an enum that has a different type of value. Their example used bytes. Your value is a str.

class MyEnum(str, Enum):
    def __new__(cls, value, extra):
        obj = str.__new__(cls, [value])
        obj._value_ = value
        obj.extra = extra
        return obj

    MEMBER = ("This is my enum", 1.5)

print(MyEnum.MEMBER)
print(MyEnum.MEMBER.value)
print(MyEnum.MEMBER.extra)

Output:
MyEnum.MEMBER
This is my enum
1.5

You were trying to create a new enum whose value was your new enum class.