def test_strange_sequence(self):
        """https://github.com/pytest-dev/pytest/issues/11797"""
        a = MyVec3(1, 2, 3)
        b = MyVec3(0, 1, 2)

        # this would trigger the error inside the test
        pytest.approx(a, abs=0.5)._repr_compare(b)

        assert b == pytest.approx(a, abs=2)
        assert b != pytest.approx(a, abs=0.5)
https://github.com/pytest-dev/pytest/issues/11797
testing/python/approx.py