docs: public DescribeClassicLinkInstancesResult withInstances(ClassicLinkInstance... instances) {
          if (this.instances == null) {
              setInstances(new com.amazonaws.internal.SdkInternalList<ClassicLinkInstance>(instances.length));
          }
          for (ClassicLinkInstance ele : instances) {
              this.instances.add(ele);
          }
          return this;
      }