I'm creating an element within an element for testing purpose:

```
const item = document.createElement("div");
// item.className("item");
item.className = "item";
const content = document.getElementsByClassName("item").appendChild("div");
content.className = "content";

```

However, I get the error:

> 
> undefined is not a constructor (evaluating 'document.getElementsByClassName("item").appendChild("div")'
> 
> 
> 

Can anyone help? 

P.S. Thanks for all the feedback!