@Override
        public Traversal<Vertex, Map<String, Map<String, Long>>> get_g_V_hasLabelXsongX_group_byXnameX_byXproperties_groupCount_byXlabelXX() {
            return g.V().hasLabel("song").<String, Map<String, Long>>group().by("name").by(__.properties().groupCount().by(T.label));
        }
@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/GroupTest.java