Got this really simple problem that I just can't figure a solution to. I am not able to call a function from another javascript file in nodejs.

My main file:

```
var Binance = require('./binance.js');

//later in the file
app.post('/createBotOrder', function (req, res, next) {
    console.log("in");
    console.log(Binance);
    console.log(Binance.sum(1, 2));
    console.log("in 2");
});

```

My secondary file:

```
module.exports = function() {
    this.sum = function(a,b) { return a+b };
    this.multiply = function(a,b) { return a*b };
    //etc
}

```

Output:

```
in
[Function]

```