docs: private T getWrappedPublisher(Publisher flexiblePublisher, Class<T> type) {
          if (!(flexiblePublisher instanceof FlexiblePublisher)) {
              throw new IllegalArgumentException(String.format("Publisher should be of type: '%s'. Found type: '%s'",
                  FlexiblePublisher.class, flexiblePublisher.getClass()));
          }
  
          List<ConditionalPublisher> conditions = ((FlexiblePublisher) flexiblePublisher).getPublishers();
          for (ConditionalPublisher condition : conditions) {
              if (type.isInstance(condition.getPublisher())) {
                  return type.cast(condition.getPublisher());
              }
          }
  
          return null;
      }