Checks the building options to make sure that they are defined last,
    after the task name and the dependencies

def _check_building_options(string):
    """
    Checks the building options to make sure that they are defined last,
    after the task name and the dependencies
    """
    opener, closer = '{', '}'
    _check_enclosing_characters(string, opener, closer)
    if opener in string:
        if string[-1] != closer:
            raise ValueError(OPTIONS_NOT_LAST)
        ret = True
    else:
        ret = False
    return ret