code: function createGraphIterators(graph) {
    return {
      /**
       * Creates a vertex iterator stream. This is an entry point for all traversal
       * starting with a node.
       *
       * @param  {string|number} [startFrom] vertex id to start iteration from.
       *  If this argument is omitted, then all graph nodes are iterated
       *
       * @returns {VertexPipe}
       */
      V: function createVertexStream(startFrom) {
        var VertexPipe = require('./lib/pipes/vertexPipe');
        var VertexIterator = require('./lib/iterators/vertexIterator');
  
        var vertexPipe = new VertexPipe(graph);
        vertexPipe.setSourcePipe(new VertexIterator(graph, startFrom));
        return vertexPipe;
      }
    };
  }
docs: Creates a wrapper to iterate over graph. A wrapper contains methods which
  allows you to begin iteration. Currently we support only vertices as iterator
  starters, but in future we can easily extend this and add edges
  
  @param {ngraph.graph|Viva.Graph.graph} graph source graph we want to iterate over