Backport PR #13614 on branch v5.0.x (MNT: Compatibility with Python 3.11) - #13664

      astropy/table/_np_utils.c:196:12: fatal error: longintrepr.h: No such file or directory
        196 |   #include "longintrepr.h"
            |            ^~~~~~~~~~~~~~~
      compilation terminated.
      error: command '/usr/bin/gcc' failed with exit code 1

    def generic_recursive_equality_test(a, b, class_history):
        """
        Check if the attributes of a and b are equal. Then,
        check if the attributes of the attributes are equal.
        """
        if PYTHON_LT_3_11:
            dict_a = a.__getstate__() if hasattr(a, '__getstate__') else a.__dict__
        else:
            # NOTE: The call may need to be adapted if other objects implementing a __getstate__
            # with required argument(s) are passed to this function.
            dict_a = a.__getstate__(a) if inspect.isclass(a) else a.__getstate__()
        dict_b = b.__dict__
>       for key in dict_a:
E       TypeError: 'NoneType' object is not iterable

FAILED astropy/cosmology/tests/test_pickle.py::test_flrw[0-FLRW-False]
FAILED astropy/cosmology/tests/test_pickle.py::test_flrw[1-FLRW-False]
FAILED astropy/cosmology/tests/test_pickle.py::test_flrw[-1-FLRW-False]

_______________________ TestFlatwCDM.test_toformat_model _______________________

self = <astropy.cosmology.tests.test_flrw.TestFlatwCDM object at 0x7fcf997acb50>
cosmo = FlatwCDM(name="ABCMeta", H0=70 km / (Mpc s), Om0=0.27, w0=-1, Tcmb0=3 K, Neff=3.04, m_nu=[0. 0. 0.] eV, Ob0=None)
to_format = <astropy.cosmology.connect.CosmologyToFormat object at 0x7fcf78113ee0>
method_name = 'Ode'

    def test_toformat_model(self, cosmo, to_format, method_name):
        """Test cosmology -> astropy.model."""
        if method_name is None:  # no test if no method
            return
    
        model = to_format("astropy.model", method=method_name)
        assert isinstance(model, _CosmologyModel)
    
        # Parameters
        expect = tuple([n for n in cosmo.__parameters__ if getattr(cosmo, n) is not None])
        assert model.param_names == expect
    
        # scalar result
        args = np.arange(model.n_inputs) + 1
    
        got = model.evaluate(*args)
        expected = getattr(cosmo, method_name)(*args)
        assert np.all(got == expected)
    
        got = model(*args)
        expected = getattr(cosmo, method_name)(*args)
>       assert np.all(got == expected)
E       assert False
E        +  where False = <function all at 0x7fcfaf7971c0>(0.2523877726514899 == 0.25238777265148993)
E        +    where <function all at 0x7fcfaf7971c0> = np.all

.../cosmology/io/tests/test_model.py:119: AssertionError