code: public OperationFuture<List<Group>> delete(Group... groups) {
          List<Group> groupList = Arrays.asList(groups);
  
          List<JobFuture> jobs = groupList.stream()
              .map(group -> delete(group).jobFuture())
              .collect(toList());
  
          return new OperationFuture<>(
              groupList,
              new ParallelJobsFuture(jobs)
          );
      }
docs: Delete set of groups
  
  @param groups groups array
  @return OperationFuture wrapper for list of groups