🔒 Enum interseting behaviour? I want to know why?

[foggy oriole]

from enum import StrEnum, auto
class Foo(StrEnum):
  A = auto()
  B = auto()
  C = auto()

# ValueError why? and why it looks like im making an instance and giving arguments but it gives back an instance of existing values only
Foo('A')

# This works
Foo('a')

# I figured out that auto when using StrEnum it uses alphabetical charecters

# Key error, i figured out that doing like that its accesing the members dictionary, so it makes sense to me
Foo['a']

# This works and ill be using that
Foo['A']

You might ask why im doing like that cuz Enums ussually are used Foo.A but im loading things from a file so i have a string value

[main cosmos]

@foggy oriole

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[real silo]

It wants equality to a value, and the auto-values here are a, b, c. You're probably looking for Foo["A"] or something like that.

[foggy oriole]

i know, but it caught my eye when testing, so i want to know why it behaves like that

[trail inlet]

!e
An enum item has two things: the "name" and the "value". For example:

from enum import Enum

class ColorChannel(Enum):
    RED = 1
    GREEN = 2
    BLUE = 69

# members are looked up by their "name"
print(ColorChannel.RED, ColorChannel.GREEN, ColorChannel.BLUE)
print(list(ColorChannel))

# but calling the enum class looks up items by value
print(ColorChannel(2))
# print(ColorChannel(3)) -- error

[main cosmos]

:white_check_mark: Your 3.12 eval job has completed with return code 0.

001 | ColorChannel.RED ColorChannel.GREEN ColorChannel.BLUE
002 | [<ColorChannel.RED: 1>, <ColorChannel.GREEN: 2>, <ColorChannel.BLUE: 69>]
003 | ColorChannel.GREEN

[trail inlet]

As you can read in https://docs.python.org/3/library/enum.html#enum.StrEnum:

Using auto with StrEnum results in the lower-cased member name as the value.

So essentially you're doing ```py
class Foo(StrEnum):
A = "a"
B = "b"
C = "c"

[foggy oriole]

well yea, but i havent found in the docs where it says that, i only found that i can access the members by key in the __getitem__ method

[trail inlet]

where it says what?

[foggy oriole]

that it checks for value when doing Test(2)

shit im blind 😄

[trail inlet]

For example: https://docs.python.org/3/howto/enum.html#enum-howto

>>> Weekday(3)
<Weekday.WEDNESDAY: 3>

[trail inlet]

Yeah, it's also written in https://docs.python.org/3/library/enum.html#enum.EnumType.__call__ but both instances are pretty vague

using __call__ for two completely different purposes is also cursed

(I'm looking at you type)

[foggy oriole]

Anyway thanks for help, now i know 😄

!close

[main cosmos]

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