@Override
    public Set<TraverserRequirement> getProvidedRequirements() {
        return REQUIREMENTS;
    }
@author Marko A. Rodriguez (http://markorodriguez.com)
gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/traverser/B_LP_O_P_S_SE_SL_TraverserGenerator.java