@Override
        public Traversal<Vertex, Integer> get_g_V_age_foldX0_plusX() {
            return g.V().<Integer>values("age").fold(0, (BinaryOperator) Operator.sum);
        }
@author Marko A. Rodriguez (http://markorodriguez.com)
gremlin-test/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/step/map/FoldTest.java