code: protected StreamingDistributionSummary getExistingDistribution(String bucketName) {
  
          List<StreamingDistributionSummary> dists =
              getAllExistingDistributions(bucketName);
          if (dists.isEmpty()) {
              return null;
          } else {
              return dists.get(0);
          }
      }
docs: /*
  Returns the first streaming distribution associated with a given bucket