Cannot create a class that supports Iterable[RichComparisonT]

Bug Report

In pandas-stubs, we'd like to be able to have a class that can be passed to the standard python sorted(), max(), min() functions, etc. But mypy doesn't seem to support this, while pyright does.

To Reproduce

from typing import TYPE_CHECKING, Iterable, Iterator, TypeVar

if TYPE_CHECKING:
    from _typeshed import SupportsRichComparisonT as SRCT
else:   # Use this to make the code runnable
    SRCT = TypeVar("SRCT")


class MyList(Iterable[SRCT]):
    def __init__(self, x: list[int]):
        self._x = x

    def __iter__(self) -> Iterator[int]:
        for i in self._x:
            yield i


foo = MyList([3, 2, 1])
print(sorted(foo))

Expected Behavior

No error reported by mypy

Actual Behavior

richcmp.py:13: error: Return type "Iterator[int]" of "__iter__" incompatible with return type "Iterator[SRCT]" in supertype "Iterable"  [override]
richcmp.py:18: error: Need type annotation for "foo"  [var-annotated]
Found 2 errors in 1 file (checked 1 source file)

Your Environment

• Mypy version used: 0.991
• Mypy command-line flags: none
• Mypy configuration options from mypy.ini (and other config files): none
• Python version used: 3.10

Comienza con la reproducción en richcmp.py y la interacción notificada entre Iterable[SupportsRichComparisonT] y iter. Compara el comportamiento de mypy con el de pyright usando el ejemplo proporcionado de Python 3.10. El trabajo estará terminado cuando el ejemplo pase la comprobación de tipos sin los errores notificados de override y anotación de variables.