How to use the actions-on-google.ActionsSdkAssistant function in actions-on-google

exports.sayNumber = functions.https.onRequest((req, res) => {
  const assistant = new ActionsSdkAssistant({request: req, response: res});

  // List of re-prompts that are used when we did not understand a number from the user.
  const reprompts = [
    'I didn\'t hear a number',
    'If you\'re still there, what\'s the number?',
    'What is the number?'
  ];

  const actionMap = new Map();

  actionMap.set(assistant.StandardIntents.MAIN, assistant => {
    const inputPrompt = assistant.buildInputPrompt(true, `
        Hi! 
        I can read out an ordinal number like 123.
        Say a number.
      `, reprompts

this.app.post('/', function (request, response) {
                _this3.assistant = new _actionsOnGoogle.ActionsSdkAssistant({ request: request, response: response });
                _this3.assistant.handleRequest(_this3.actionsMap);
            });
        }

router.post('/', (req, res) => {
            this.assistant = new actionsSdk.ActionsSdkAssistant({ request: req, response: res });
            this.assistant.handleRequest(this.actionsMap);
            res.sendStatus(200);
        });
        return router;

this.app.post('/', (request, response) => {
            this.assistant = new ActionsSdkAssistant({ request, response });
            this.assistant.handleRequest(this.actionsMap);
        });
    }

router.post("/", (req, res) => {
            this.assistant = new actionsSdk
                .ActionsSdkAssistant({ request: req, response: res });
            this.assistant.handleRequest(this.actionsMap);
        });
        this.express.use("/", router);

router.post('/', (req, res) => {
      this.assistant = new actionsSdk.ActionsSdkAssistant({request: req, response: res});
      this.assistant.handleRequest(this.actionsMap);
      res.sendStatus(200);
    });