movieCredits(identifier) {
    const query = { id: identifier }
    const cacheKey = `tmdb/${this.cacheTags.movieCredits}:${identifier}`

    return this.getFromCacheOrFetchFromTmdb(cacheKey, 'movieCredits', query)
      .then(credits => this.cache.set(cacheKey, credits, this.defaultTTL))
      .then(credits => Credits.convertFromTmdbResponse(credits))
  }
/**
   * Retrieve credits for a movie
   * @param {Number} identifier of the movie to get credits for
   * @returns {Promise} movie cast object
   */
Retrieve credits for a movie
@param {Number} identifier of the movie to get credits for
@returns {Promise} movie cast object
Retrieve credits for a movie @param { Number } identifier of the movie to get credits for @returns { Promise } movie cast object
movieCredits(identifier) {
    const query = { id: identifier }
    const cacheKey = `tmdb/${this.cacheTags.movieCredits}:${identifier}`
    return this.getFromCacheOrFetchFromTmdb(cacheKey, 'movieCredits', query)
      .then(credits => this.cache.set(cacheKey, credits, this.defaultTTL))
      .then(credits => Credits.convertFromTmdbResponse(credits))
  }
movieCredits ( identifier ) { const query = { id : identifier } const cacheKey = ` ${ this . cacheTags . movieCredits } ${ identifier } ` return this . getFromCacheOrFetchFromTmdb ( cacheKey , 'movieCredits' , query ) . then ( credits => this . cache . set ( cacheKey , credits , this . defaultTTL ) ) . then ( credits => Credits . convertFromTmdbResponse ( credits ) ) }
Retrieve credits for a movie
 @param {Number} identifier of the movie to get credits for
 @returns {Promise} movie cast object
Retrieve credits for a movie @param { Number } identifier of the movie to get credits for @returns { Promise } movie cast object