You have *path operations* for:

* `/items/`
* `/items/{item_id}`

It's all the same structure as with `app/routers/users.py`.

But we want to be smarter and simplify the code a bit.

We know all the *path operations* in this module have the same:

* Path `prefix`: `/items`.
* `tags`: (just one tag: `items`).
* Extra `responses`.