How to use the feed.feed function in feed

, function (require, exports, module) {
        var feed = require("feed").feed
            , Backbone = require("backbone")
            , TweetView = require("tweetView").TweetView

            // The FeedView is a simple container of TweetViews and therefore
            // doesn't need a template. The ul element provided by the Backbone
            // View is sufficient.
            , FeedView = Backbone.View.extend({
                tagName: "ul"
                , className: "feed"

                , initialize: function() {
                    // Bind to model changes
                    feed.bind('add',   this.addTweet, this);
                    feed.bind('reset', this.addAll,   this);

                    // Load stored tweets from local storage

, function (require, exports, module) {
        var twig = require("twig").twig
            , Backbone = require("backbone")
            , feed = require("feed").feed

            // The application template
            , template = twig({
                href: 'templates/app.twig'
                , async: false
            })
            
            , FeedView = require("feedView").FeedView
            , feedView = new FeedView

            , AppView = Backbone.View.extend({
                tagName: "div"
                , className: "app"

                // Bind to the buttons in the template
                , events: {