How to extend the events method of a view – eg

_.extend(InvoiceDetailsView.prototype, {            

               events: _.extend(InvoiceDetailsView.prototype.events, {                       

                              ‘change [data-action=”filechange”]’: ‘filechange’,                       

                              ‘click [data-action=”pofile”]’: ‘pofile’

               }),

               filechange: function(input) {….},

               pofile: function(input) {….}

}