def extract_subtypes(mappings, data_type):
    """Extract subtypes of given data types. e.g: for data type "alert", possible subtypes are "dlp", "policy" etc.

    :param mapping_file: Path to JSON mapping file
    :param data_type: data type for which subtypes are to be fetched
    :return: extracted sub types
    """
    taxonomy = mappings["taxonomy"].get(data_type, {})
    return [subtype for subtype in taxonomy]