def split(header):
    match = headerValue.match(header)
    if not match:
        return (None, None)
    return match.group(1).lower(), header[match.end():]
>>> t = MediaFileBase()
dataset/ETHPy150Open mailgun/flanker/flanker/mime/message/headers/parametrized.py/split--crossover with--dataset/ETHPy150Open feincms/feincms/feincms/module/medialibrary/models.py/MediaFileBase.determine_file_type