docs: public Waiter<DescribeInstancesRequest> instanceExists() {
  
          return new WaiterBuilder<DescribeInstancesRequest, DescribeInstancesResult>().withSdkFunction(new DescribeInstancesFunction(client))
                  .withAcceptors(new InstanceExists.IsTrueMatcher(), new InstanceExists.IsInvalidInstanceIDNotFoundMatcher())
                  .withDefaultPollingStrategy(new PollingStrategy(new MaxAttemptsRetryStrategy(40), new FixedDelayStrategy(5)))
                  .withExecutorService(executorService).build();
      }