@Override
        public Traversal<Vertex, Long> get_g_V_unionXoutXknowsX__outXcreatedX_inXcreatedXX_groupCount_selectXvaluesX_unfold_sum() {
            return g.V().union(out("knows"), out("created").in("created")).groupCount().select(Column.values).unfold().sum();
        }
@author Marko A. Rodriguez (http://markorodriguez.com)
@author Stephen Mallette (http://stephen.genoprime.com)
gremlin-test/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/step/sideEffect/GroupCountTest.java