presto-raptor-legacy/src/main/java/io/prestosql/plugin/raptor/legacy/metadata/BucketShards.java/BucketShards/toString
class BucketShards:    @Override
    public String toString()
    {
        return toStringHelper(this)
                .add("bucketNumber", bucketNumber.isPresent() ? bucketNumber.getAsInt() : null)
                .add("shards", shards)
                .omitNullValues()
                .toString();
    }