docs: public static Map<String, String> extractFrom(Function<String, String> env) {
      Map<String, String> headers = new LinkedHashMap<>();
      addHeader(headers, env, NetflixHeader.ASG, NETFLIX_ASG);
      addHeader(headers, env, NetflixHeader.Node, NETFLIX_NODE);
      addHeader(headers, env, NetflixHeader.Zone, NETFLIX_ZONE);
      return headers;
    }