class AttachmentUploadResult {

    public Set<AttachmentUploadRequest.Item> successfulUploads() {
        return successfulUploads;
    }

    public  AttachmentUploadResult(T target);
    private  AttachmentUploadResult(T target,
                                   Set<AttachmentUploadRequest.Item> successfulUploads,
                                   Map<AttachmentUploadRequest.Item, Throwable> failedUploads);

}