code: public OperationFuture<List<Server>> removePublicIp(Server... servers) {
          checkNotNull(servers, "Server references must be not null");
          List<Server> serverList = Arrays.asList(servers);
  
          List<JobFuture> futures = serverList.stream()
              .map(serverRef -> removePublicIp(serverRef).jobFuture())
              .collect(toList());
  
          return new OperationFuture<>(
              serverList,
              new ParallelJobsFuture(futures)
          );
      }
docs: Remove all public IPs from servers array
  
  @param servers server references
  @return OperationFuture wrapper for list of ServerRef