Inconsistent dataclass order behavior on Python 3.13+

Bug report

Bug description:

Semantics of dataclasses __eq__ have changed in Python 3.13+, the semantic is now inconsistent with the order=True generated set of dunder methods on the same Python 3.13+ versions.

Related issues:
#128294
#120645

@dataclasses.dataclass(order=True)
class Data:
    a: float

nan = float("nan")

assert not (Data(nan) < Data(nan))
# assert not (Data(nan) <= Data(nan)), "fails on 3.13 even though {<, ==} are both False"
assert not (Data(nan) > Data(nan))
# assert not (Data(nan) >= Data(nan)), "fails on 3.13 even though {>, ==} are both False"
assert (Data(nan) != Data(nan))
assert not (Data(nan) == Data(nan))

Proposed fix PR: #137497

CPython versions tested on:

3.13

Operating systems tested on:

Windows

Linked PRs

• gh-137497

Start by reproducing the dataclasses order comparisons in the issue on Python 3.13+, then read related issues #128294 and #120645 and the proposed fix in PR #137497. Done means the generated ordering comparisons have consistent behavior with equality for NaN values, with regression coverage for the reported assertions.