presto-thrift-api/src/main/java/io/prestosql/plugin/thrift/api/valuesets/PrestoThriftRangeValueSet.java/PrestoThriftRangeValueSet/toString
class PrestoThriftRangeValueSet:        @Override
        public String toString()
        {
            return toStringHelper(this)
                    .add("low", low)
                    .add("high", high)
                    .toString();
        }