presto-main/src/main/java/io/prestosql/sql/planner/PlanFragment.java/PlanFragment/withBucketToPartition
class PlanFragment:    public PlanFragment withBucketToPartition(Optional<int[]> bucketToPartition)
    {
        return new PlanFragment(id, root, symbols, partitioning, partitionedSources, partitioningScheme.withBucketToPartition(bucketToPartition), stageExecutionDescriptor, statsAndCosts, jsonRepresentation);
    }