Incompatible typing for `logging.Formatter.converter` and `time.gmtime`/`time/localtime` ?

The typing for converter here is as follows:

converter: Callable[[float | None], struct_time]

And the typing for time.gmtime/time.localtime here is:

def gmtime(seconds: float | None = None, /) -> struct_time: ...
def localtime(seconds: float | None = None, /) -> struct_time: ...

Yet when I try to typecheck this code:

import logging
import time

class UTCFormatter(logging.Formatter):
    converter = time.gmtime

I get the following error:

$ mypy main.py
main.py:5: error: Incompatible types in assignment (expression has type "Callable[[], struct_time]", base class "Formatter" defined the type as "Callable[[float | None], struct_time]")  [assignment]
Found 1 error in 1 file (checked 1 source file)

I tested this on a fresh python3.13 venv with the following deps installed:

mypy==1.18.2
mypy_extensions==1.1.0
pathspec==0.12.1
typing_extensions==4.15.0

参照されている定義の stdlib/logging/init.pyi と stdlib/time.pyi から始め、issue の例を使って mypy で代入を再現します。2 つの callable アノテーションが互換性のないものとして扱われる理由を確認し、代入エラーなしで例の型チェックが通るように、該当する stub の型付けを更新します。