docs: public Graph<K, VV, EV> addVertices(List<Vertex<K, VV>> verticesToAdd) {
  		// Add the vertices
  		DataSet<Vertex<K, VV>> newVertices = this.vertices.coGroup(this.context.fromCollection(verticesToAdd))
  				.where(0).equalTo(0).with(new VerticesUnionCoGroup<>()).name("Add vertices");
  
  		return new Graph<>(newVertices, this.edges, this.context);
  	}