code: public Observable<SoundCloudUser> getArtistProfile() {
          checkState();
          if (mCacheRam.artistProfile != null) {
              return Observable.create(new Observable.OnSubscribe<SoundCloudUser>() {
                  @Override
                  public void call(Subscriber<? super SoundCloudUser> subscriber) {
                      subscriber.onNext(mCacheRam.artistProfile);
                      subscriber.onCompleted();
                  }
              });
          } else {
              return mRetrofitService.getUser(mArtistName)
                      .map(RxParser.PARSE_USER)
                      .map(cacheArtistProfile());
          }
      }
docs: Retrieve SoundCloud artist profile.
  
  @return {@link rx.Observable} on {@link SoundCloudUser}