Have an automatic API documentation web user interface.

### <a href="https://flask.palletsprojects.com" class="external-link" target="_blank">Flask</a>

Flask is a "microframework", it doesn't include database integrations nor many of the things that come by default in Django.

This simplicity and flexibility allow doing things like using NoSQL databases as the main data storage system.

* A particular program while it is **running** on the operating system.
    * This doesn't refer to the file, nor to the code, it refers **specifically** to the thing that is being **executed** and managed by the operating system.
* Any program, any code, **can only do things** when it is being **executed**. So, when there's a **process running**.

But now you know how it works, so you can use relative imports in your own apps no matter how complex they are. 🤓

### Add some custom `tags`, `responses`, and `dependencies`

We are not adding the prefix `/items` nor the `tags=["items"]` to each *path operation* because we added them to the `APIRouter`.

* **Ajohunše/Ìtọ́kasí**: Ó da lori (àti ibamu ni kikun pẹ̀lú) àwọn ìmọ ajohunše/ìtọ́kasí fún àwọn API: <a href="https://github.com/OAI/OpenAPI-Specification" class="external-link" target="_blank">OpenAPI</a> (èyí tí a mọ tẹlẹ si Swagger) àti <a href="https://json-schema.org/" class="external-link" target="_blank">JSON Schema</a>.