public List<Traversal.Admin<?, ?>> getGlobalChildren() {
        return Collections.singletonList(this.computerTraversal.get());
    }
@author Marko A. Rodriguez (http://markorodriguez.com)
gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/process/computer/traversal/step/map/TraversalVertexProgramStep.java