presto-main/src/main/java/io/prestosql/sql/planner/optimizations/StreamPropertyDerivations.java/StreamPropertyDerivations/toString
class StreamPropertyDerivations:        @Override
        public String toString()
        {
            return toStringHelper(this)
                    .add("distribution", distribution)
                    .add("partitioningColumns", partitioningColumns)
                    .toString();
        }