def from_json_file(cls, json_file: Union[str, os.PathLike]) -> PreTrainedFeatureExtractor:
        """
        Instantiates a feature extractor of type [`~feature_extraction_utils.FeatureExtractionMixin`] from the path to
        a JSON file of parameters.

        Args:
            json_file (`str` or `os.PathLike`):
                Path to the JSON file containing the parameters.

        Returns:
            A feature extractor of type [`~feature_extraction_utils.FeatureExtractionMixin`]: The feature_extractor
            object instantiated from that JSON file.
        """
        with open(json_file, "r", encoding="utf-8") as reader:
            text = reader.read()
        feature_extractor_dict = json.loads(text)
        return cls(**feature_extractor_dict)

        Instantiates a feature extractor of type [`~feature_extraction_utils.FeatureExtractionMixin`] from the path to
        a JSON file of parameters.

        Args:
            json_file (`str` or `os.PathLike`):
                Path to the JSON file containing the parameters.

        Returns:
            A feature extractor of type [`~feature_extraction_utils.FeatureExtractionMixin`]: The feature_extractor
            object instantiated from that JSON file.
        
dpkd/transformers/src/transformers/feature_extraction_utils.py