PLW3201 flags _missing_ in Enum subclass

[mal]

Enum in Python has a few supported sunder names. Of them, _missing_ and _generate_next_value_ are explicitly called out as overridable but when doing so they get flagged as misspelled dunder methods.

Looks separate from, but related to #4592.

from enum import StrEnum
class Build(StrEnum):
    @classmethod
    def _missing_(cls, value):
        pass

$ ruff --isolated --preview --select PLW3201 --show-source test.py
test.py:4:9: PLW3201 Bad or misspelled dunder method name `_missing_`. (bad-dunder-name)
  |
2 | class Build(StrEnum):
3 |     @classmethod
4 |     def _missing_(cls, value):
  |         ^^^^^^^^^ PLW3201
5 |         pass
  |

Observed using ruff 0.0.292.

[charliermarsh]

Thanks!