[Python] What should typing be for __add__ in a subclass of list?

This is a simplification of my code:

# my_list.py
from __future__ import annotations


class MyList(list[int]):
def __add__(self, other: list[int]) -> MyList:
return MyList()


mypy says:

> mypy .\my_list.py --strict
my_list.py:5: error: Signature of "__add__" incompatible with supertype "list" [override]
my_list.py:5: note: Superclass:
my_list.py:5: note: @overload
my_list.py:5: note: def __add__(self, list[int], /) -> list[int]
my_list.py:5: note: @overload
my_list.py:5: note: def [_S] __add__(self, list[_S], /) -> list[_S | int]
my_list.py:5: note: Subclass:
my_list.py:5: note: def __add__(self, list[int], /) -> MyList


If I do this, mypy no longer complains:

from typing import overload, TypeVar

_T = TypeVar("_T")

class MyList(list[int]):
@overload
def __add__(self, other: list[int]) -> list[int]:
...

@overload
def __add__(self, other: list[_T]) -> list[_T | int]:
...

def __add__(self, other: list[_T] | list[int]) -> list[_T | int]:
return [0]


... but then it doesn't really make sense for addition of MyLists to return lists...

Also, the problem gets much worse if we try to add a __iadd__ method... Then it either says that its signature isn't compatible with that of __add__, or is incompatible with some superclass's signature...

Signature of "__iadd__" incompatible with "__add__" of supertype "list" [override]
Signatures of "__iadd__" and "__add__" are incompatible [misc]


To me things should be really simple here, but they're not. Also I am aware of the Liskov Substitution Principle, and I think I've taken it into account for all of my tests.

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