old_contents: define(function (require) {
  
      var Backbone = require('backbone'),
          _ = require('underscore'),
          globals = require('globals'),
          Instance = require('models/Instance'),
          VolumeState = require('./VolumeState');
  
      return Backbone.Model.extend({
        urlRoot: globals.API_V2_ROOT + "/volumes",
  
        parse: function (attributes) {
          attributes.start_date = new Date(attributes.start_date);
          attributes.state = new VolumeState({status_raw: attributes.status});
          attributes.status = attributes.status || "Unknown";
  
          if (attributes.attach_data && attributes.attach_data.instance_alias) {
            attributes.attach_data = {
              device: attributes.attach_data.device,
              instance_id: attributes.attach_data.instance_alias
            };
          }else{
            attributes.attach_data = {
              device: null,
              instance_id: null
            };
          }
  
          return attributes;
        },
  
        isAttached: function () {
          return this.get('status') == 'in-use' || this.get('status') == 'detaching';
        }
  
      });
  
    });
  
new_contents: define(function (require) {
  
    var Backbone = require('backbone'),
        globals = require('globals'),
        VolumeState = require('./VolumeState');
  
    return Backbone.Model.extend({
      urlRoot: globals.API_V2_ROOT + "/volumes",
  
      parse: function (attributes) {
        attributes.start_date = new Date(attributes.start_date);
        attributes.state = new VolumeState({status_raw: attributes.status});
        attributes.status = attributes.status || "Unknown";
  
        if (attributes.attach_data && attributes.attach_data.instance_alias) {
          attributes.attach_data = {
            device: attributes.attach_data.device,
            instance_id: attributes.attach_data.instance_alias
          };
        }else{
          attributes.attach_data = {
            device: null,
            instance_id: null
          };
        }
  
        return attributes;
      },
  
      isAttached: function () {
        return this.get('status') == 'in-use' || this.get('status') == 'detaching';
      }
  
    });
  
  });
  
subject: switch to commonJS format