code: public static <T> HttpResponse fromPublisher(Publisher<T> contentPublisher,
                                                   Function<? super T, ? extends ServerSentEvent> converter) {
          return fromPublisher(defaultHttpHeaders, contentPublisher, HttpHeaders.EMPTY_HEADERS, converter);
      }
docs: Creates a new Server-Sent Events stream from the specified {@link Publisher} and {@code converter}.
  
  @param contentPublisher the {@link Publisher} which publishes the objects supposed to send as contents
  @param converter the converter which converts published objects into {@link ServerSentEvent}s