def METHOD_NAME(self):
    """Find and process metadata file.
    Try to find metadata json file in job folder to get context from.
    Returns:
        dict: Context from metadata json file.
    """
    image_dir = self.job.imageDir
    metadata_files = glob.glob(
        "{}{}*_metadata.json".format(image_dir, os.path.sep))
    if not metadata_files:
        return {}
    raise NotImplementedError(
        "Processing existing metadata not implemented yet.")