ReferenceError: request is not defined in NodeJS Session

I am new in NodeJS and I'm trying to work with session. But I am stuck with this error. Any kind of help is appreciated.

Code :-

var express = require('express');
var jsonFile = require('jsonfile');
var NodeSession = require('node-session');
var router = express.Router();

session = new NodeSession({secret: 'Q3UBzdH9GEfiRCTKbi5MTPyChpzXLsTD', 'lifetime': 60 * 1000, 'secure': true, 'encrypt': true});

session.startSession(request, response, function () {
    // server handler goes here
    // req.session available
});

function restrict(req, res, next) {
    if (req.session.has('sessnm')) {
        next();
    } else {
        res.redirect('/');
}

It shows me the error in this line:-

session.startSession(request, response, function () {

via Yash Parekh