How to use the argo-ui/src/index.NotificationType.Success function in argo-ui

private async changePassword(username: string, currentPassword: Nested | FormValue, newPassword: Nested | FormValue) {
        try {
            await services.accounts.changePassword(username, currentPassword, newPassword);
            this.appContext.apis.notifications.show({type: NotificationType.Success, content: 'Your password has been successfully updated.'});
            this.showChangePassword = false;
        } catch (e) {
            this.appContext.apis.notifications.show({
                content: ,
                type: NotificationType.Error
            });
        }
    }