How to use the kibitzr.exceptions.ConfigurationError function in kibitzr

def _clean_single_schedule(cls, check, schedule_dict):
        if not isinstance(schedule_dict, dict):
            raise ConfigurationError(
                'Check {0} has invalid schedule configuration: {1}'
                .format(check['name'], schedule_dict),
            )
        try:
            every = schedule_dict['every']
        except KeyError:
            raise ConfigurationError(
                "Check {0} has invalid schedule format: {1}"
                .format(check['name'], schedule_dict)
            )
        if isinstance(every, six.string_types):
            # "every: day" shortcut
            unit, every = every, 1
        else:
            unit = schedule_dict.get('unit')
        unit = cls._clean_unit(check, unit)

def _clean_unit(check, unit):
        try:
            getattr(schedule.every(1), unit)
        except:
            raise ConfigurationError(
                "Unit {0} is not one of valid options. Referenced in check {1}"
                .format(unit, check['name'])
            )
        return unit

def fetcher_factory(conf):
    """Return initialized fetcher capable of processing given conf."""
    global PROMOTERS
    applicable = []
    if not PROMOTERS:
        PROMOTERS = load_promoters()
    for promoter in PROMOTERS:
        if promoter.is_applicable(conf):
            applicable.append((promoter.PRIORITY, promoter))
    if applicable:
        best_match = sorted(applicable, reverse=True)[0][1]
        return best_match(conf)
    else:
        raise ConfigurationError(
            'No fetcher is applicable for "{0}"'.format(conf['name'])
        )

def _clean_at(cls, check, at):
        if at is None or cls.RE_TIME.match(at):
            return at
        raise ConfigurationError(
            'Check {0} schedule has invalid value for "at": {1}'
            .format(check['name'], at)
        )

unit='seconds',
                at=None
            ))
        if "schedule" in check:
            schedule_value = check['schedule']
            if isinstance(schedule_value, dict):
                check_schedule.append(
                    cls._clean_single_schedule(check, schedule_value)
                )
            elif isinstance(schedule_value, list):
                check_schedule.extend([
                    cls._clean_single_schedule(check, item)
                    for item in schedule_value
                ])
            else:
                raise ConfigurationError(
                    'Check {0} has invalid schedule configuration: {1}'
                    .format(check['name'], check['schedule'])
                )
        return check_schedule