def METHOD_NAME(cls, level):
    """Converts a type CompletenessLevel to type str.
    For example, if input is CompletenessLevel.basic, this method will return "basic."
    Arguments:
        level - An enum value of type CompletenessLevel
    Returns:
        CompletenessLevel as a string
    """
    if not isinstance(level, CompletenessLevel):
        logging.error("Invalid completeness type. Expected: {}. Format {}"
                      .format(str(CompletenessLevel), type(level)))
    level_name = level.name.lower()
    return level_name