presto-main/src/main/java/io/prestosql/operator/aggregation/NumericHistogram.java/Entry/toString
class Entry:        @Override
        public String toString()
        {
            return toStringHelper(this)
                    .add("id", id)
                    .add("value", value)
                    .add("weight", weight)
                    .add("penalty", penalty)
                    .add("valid", valid)
                    .toString();
        }