How to use the multidict.MultiMapping function in multidict

def test_abc_inheritance():
    assert issubclass(MultiMapping, Mapping)
    assert not issubclass(MultiMapping, MutableMapping)
    assert issubclass(MutableMultiMapping, Mapping)
    assert issubclass(MutableMultiMapping, MutableMapping)

def test_generic_type_in_runtime():
    MultiMapping[str]
    MutableMultiMapping[str]

+ [(PyMultiDictProxy, PyMultiDict), (PyCIMultiDictProxy, PyCIMultiDict)],
    ids=(["MultiDictProxy", "CIMultiDictProxy"] if USE_CYTHON else [])
    + ["PyMultiDictProxy", "PyCIMultiDictProxy"],
)
def proxy_classes(request):
    return request.param


def test_abc_inheritance():
    assert issubclass(MultiMapping, Mapping)
    assert not issubclass(MultiMapping, MutableMapping)
    assert issubclass(MutableMultiMapping, Mapping)
    assert issubclass(MutableMultiMapping, MutableMapping)


class A(MultiMapping):
    def __getitem__(self, key):
        pass

    def __iter__(self):
        pass

    def __len__(self):
        pass

    def getall(self, key, default=None):
        super().getall(key, default)

    def getone(self, key, default=None):
        super().getone(key, default)