code: function (name, parent_id, done, config) {
          if (!_.isString(name) || !_.isNumber(parseInt(parent_id, 10))) {
            return done(new Error('Invalid params. Required - name: string, parent_id: number'));
          }
          this._request(['folders'], 'POST', done, null, {
            name: name,
            parent: {
              id: parent_id.toString()
            }
          }, null, null, null, config);
        }
docs: Used to create a new empty folder. The new folder will be created inside of the
  specified parent folder.
  @summary Create a New Folder.
  @see {@link https://developers.box.com/docs/#folders-create-a-new-folder}
  @param {string} name - The folder's name.
  @param {number} parent_id - The parent folder's ID.
  @param {requestCallback} done - The callback to invoke (with possible errors) when the request returns.
  @param {?RequestConfig} [config] - Configure the request behaviour.