Can any one help me please.

I have this function in my module.js :

      init: function () {
            this._super.apply(this, arguments);
        var self = this;
            this._start = null;
            this._watch = null;
        var Model = new instance.web.Model(new_class);

        },

But when i do :  this.field_manager.set_values({matricule}) (matricule exists in new_class table.

I have this error : Uncaught TypeError: Cannot read property 'get_field_value' of undefined