How to use the angular-l10n.LogLevel.Warn function in angular-l10n

import { NgxMdModule } from 'ngx-md';
import { FhqJuryAdComponent } from './pages/fhq-jury-ad/fhq-jury-ad.component';
import { SimplemdeModule } from 'ng2-simplemde'

/*import hljs from 'highlight.js/lib/highlight';
import javascript from 'highlight.js/lib/languages/javascript';
import typescript from 'highlight.js/lib/languages/typescript';
hljs.registerLanguage('javascript', javascript);
hljs.registerLanguage('typescript', typescript);*/

const DEFAULT_ACE_CONFIG: AceConfigInterface = {
};

const l10nConfig: L10nConfig = {
    logger: {
        level: LogLevel.Warn
    },
    locale: {
        languages: [
            { code: 'en', dir: 'ltr' },
            { code: 'it', dir: 'ltr' }
        ],
        language: 'en',
        storage: StorageStrategy.Cookie
    },
    translation: {
        providers: [
            { type: ProviderType.Static, prefix: './assets/locale-' }
        ],
        caching: true,
        composedKeySeparator: '.',
        missingValue: 'No key',