def string_from_uuid(uuid_obj):
    """Returns standard hexadecimal string for uuid; same as str(uuid_obj).

    arguments:
       uuid_obj (uuid.UUID object): the uuid which is required in hexadecimal string format

    returns:
       string (40 characters: 36 lowercase hexadecimals and 4 hyphens)
    """

    return str(uuid_obj)