How to use the jsons._compatibility_impl.get_type_hints function in jsons

def test_simple_dump_and_load_dataclass(self):

        class C:
            pass

        hints = get_type_hints(C.__init__)
        self.assertDictEqual({}, hints)

def _get_attributes_and_types(cls: type,
                              strict: bool) -> Dict[str, Optional[type]]:
    if '__slots__' in cls.__dict__:
        attributes = {attr: None for attr in cls.__slots__}
    elif hasattr(cls, '__annotations__'):
        # Fixme: remove code below if tests succeed on all platforms.
        # attributes = cls.__annotations__
        attributes = get_type_hints(cls)
    elif strict:
        hints = get_type_hints(cls.__init__)
        attributes = {k: hints[k] for k in hints if k != 'self'}
    else:
        attributes = {}

    # Add properties and class variables.
    props, class_vars = _get_class_props(cls)
    for elem in props + class_vars:
        attributes[elem] = None

    return attributes

def _get_constructor_args(
        obj,
        cls,
        meta_hints,
        attr_getters=None,
        **kwargs) -> dict:
    # Loop through the signature of cls: the type we try to deserialize to. For
    # every required parameter, we try to get the corresponding value from
    # json_obj.
    signature_parameters = _get_signature(cls)
    hints = get_type_hints(cls.__init__)
    attr_getters = dict(**(attr_getters or {}))

    result = {}
    for sig_key, sig in signature_parameters.items():
        if sig_key != 'self':
            key, value = _get_value_for_attr(obj=obj,
                                             orig_cls=cls,
                                             meta_hints=meta_hints,
                                             attr_getters=attr_getters,
                                             sig_key=sig_key,
                                             cls=hints.get(sig_key, None),
                                             sig=sig,
                                             **kwargs)
            if key:
                result[key] = value
    return result

def _get_attributes_and_types(cls: type,
                              strict: bool) -> Dict[str, Optional[type]]:
    if '__slots__' in cls.__dict__:
        attributes = {attr: None for attr in cls.__slots__}
    elif hasattr(cls, '__annotations__'):
        # Fixme: remove code below if tests succeed on all platforms.
        # attributes = cls.__annotations__
        attributes = get_type_hints(cls)
    elif strict:
        hints = get_type_hints(cls.__init__)
        attributes = {k: hints[k] for k in hints if k != 'self'}
    else:
        attributes = {}

    # Add properties and class variables.
    props, class_vars = _get_class_props(cls)
    for elem in props + class_vars:
        attributes[elem] = None

    return attributes