@NonNull
    public Builder setNetworkFetcher(@NonNull LottieNetworkFetcher fetcher) {
      this.networkFetcher = fetcher;
      return this;
    }
Lottie has a default network fetching stack built on {@link java.net.HttpURLConnection}. However, if you would like to hook into your own
network stack for performance, caching, or analytics, you may replace the internal stack with your own.
lottie/src/main/java/com/airbnb/lottie/LottieConfig.java