A function to load a previously saved ImageClassifier
        instance.

        Parameters
        ----------
        unpickler : GLUnpickler
            A GLUnpickler file handler.

        version : int
            Version number maintained by the class writer.

def _load_version(cls, state, version):
        """
        A function to load a previously saved ImageClassifier
        instance.

        Parameters
        ----------
        unpickler : GLUnpickler
            A GLUnpickler file handler.

        version : int
            Version number maintained by the class writer.
        """
        _tkutl._model_version_check(version, cls._PYTHON_IMAGE_SIMILARITY_VERSION)
        from turicreate.toolkits.nearest_neighbors import NearestNeighborsModel
        state['similarity_model'] = NearestNeighborsModel(state['similarity_model'])

        # Correct models saved with a previous typo
        if state['model'] == "VisionFeaturePrint_Screen":
            state['model'] = "VisionFeaturePrint_Scene"

        if state['model'] == "VisionFeaturePrint_Scene" and _mac_ver() < (10,14):
            raise ToolkitError("Can not load model on this operating system. This model uses VisionFeaturePrint_Scene, "
                               "which is only supported on macOS 10.14 and higher.")
        state['feature_extractor'] = _image_feature_extractor._create_feature_extractor(state['model'])
        state['input_image_shape'] = tuple([int(i) for i in state['input_image_shape']])
        return ImageSimilarityModel(state)