There is this code:

```
const stats = {
max: 56.78,
standard_deviation: 4.34,
median: 34.54,
mode: 23.87,
min: -0.75,
average: 35.85
};
const half = (function() {
"use strict"; // do not change this line
// change code below this line
return function half(stats) {
// use function argument destructuring
return (stats.max + stats.min) / 2.0;
};
// change code above this line
})();
console.log(stats); // should be object
console.log(half(stats)); // should be 28.015
```

Why we return a function and what can we do with it? And why we have two half functions? And why we store the function in the constant?