I have following code with async function download\_file(), its working correctly only where runs as single, but in loop, it's not waiting end of iteration.
<https://pastebin.com/PRgJRn9i>

```
(async () => {

  for (let year of years) {
    for (let month of months) {
        for (let r of day_rng) {
           await download_file(year, month, r);
          }
    }
  }

})();

```