You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: module.go
    path of file: ./repos/portmaster/intel/filterlists
    
    the code of the file until where you have to start completion: package filterlists


    
func start() error {
	filterListLock.Lock()
	defer filterListLock.Unlock()

	ver, err := getCacheDatabaseVersion()
	if err == nil {
		log.Debugf("intel/filterlists: cache database has version %s", ver.String())

		if err = defaultFilter.loadFromCache(); err != nil {
			err = fmt.Errorf("failed to initialize bloom filters: %w", err)
		}
	}

	if err != nil {
		log.Debugf("intel/filterlists: blocklists disabled, waiting for update (%s)", err)
		warnAboutDisabledFilterLists()
	} else {
		log.Debugf("intel/filterlists: using cache database")
		close(filterListsLoaded)
	}

	return nil
}