nodejs Route.get() requires callback functions but got a [object String]

I'm starting coding using nodejs with express. So i did this in my file test.js which is into my folder routes :

const express = require('express');

const router = new express.Router();

router.get('/test', (req, res) => { res.send(I'm a test); });

module.exports = router;

Then, in my server.js :

const test = require('./server/routes/test'); app.use('/test', test);

In my browser, it tells me Cannot get/test

I don't understand why. Need for help. Thanks

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