@Override
    public void setParent(final TraversalParent step) {
        if (null != this.bypassTraversal) {
            this.bypassTraversal.setParent(step);
            step.integrateChild(this.bypassTraversal);
        }
    }
@author Marko A. Rodriguez (http://markorodriguez.com)
gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/lambda/AbstractLambdaTraversal.java