That's why in this example we have to declare it in the `response_model` parameter.

...but continue reading below to see how to overcome that.

## Return Type and Data Filtering

Let's continue from the previous example. We wanted to **annotate the function with one type** but return something that includes **more data**.

### <a href="https://webargs.readthedocs.io/en/latest/" class="external-link" target="_blank">Webargs</a>

Another big feature required by APIs is <abbr title="reading and converting to Python data">parsing</abbr> data from incoming requests.

Webargs is a tool that was made to provide that on top of several frameworks, including Flask.

!!! check "😮 **FastAPI** "
    ⚙️ 📟 🔬 "🔗" 👈 🚚 💽 🆎 & 🔬, 🔁.

### <a href="https://webargs.readthedocs.io/en/latest/" class="external-link" target="_blank">Webarg</a>

➕1️⃣ 🦏 ⚒ ✔ 🔗 <abbr title="reading and converting to Python data">✍</abbr> 📊 ⚪️➡️ 📨 📨.

Webarg 🧰 👈 ⚒ 🚚 👈 🔛 🔝 📚 🛠️, 🔌 🏺.

⚫️ ⚙️ 🍭 🔘 💽 🔬. &amp; ⚫️ ✍ 🎏 👩‍💻.

⚫️ 👑 🧰 &amp; 👤 ✔️ ⚙️ ⚫️ 📚 💁‍♂️, ⏭ ✔️ **FastAPI**.

!!! info

## Recap

You have been reading here some of the main concepts that you would probably need to keep in mind when deciding how to deploy your application:

* Security - HTTPS
* Running on startup
* Restarts

### Create Pydantic *models* / schemas for reading / returning

Now create Pydantic *models* (schemas) that will be used when reading data, when returning it from the API.

For example, before creating an item, we don't know what will be the ID assigned to it, but when reading it (when returning it from the API) we will already know its ID.

### Creating the `Settings` only once with `lru_cache`

Reading a file from disk is normally a costly (slow) operation, so you probably want to do it only once and then re-use the same settings object, instead of reading it for each request.

But every time we do:

```Python
Settings()
```

* **Intuitive**: Great editor support. <abbr title="also known as auto-complete, autocompletion, IntelliSense">Completion</abbr> everywhere. Less time debugging.
* **Easy**: Designed to be easy to use and learn. Less time reading docs.
* **Short**: Minimize code duplication. Multiple features from each parameter declaration. Fewer bugs.
* **Robust**: Get production-ready code. With automatic interactive documentation.

### What are "Context Managers"

"Context Managers" are any of those Python objects that you can use in a `with` statement.

For example, <a href="https://docs.python.org/3/tutorial/inputoutput.html#reading-and-writing-files" class="external-link" target="_blank">you can use `with` to read a file</a>:

```Python
with open("./somefile.txt") as f:
    contents = f.read()
    print(contents)
```

🚥 👆 👟 ⚪️➡️ ➕1️⃣ 🔁 🛠️ 👈 🔨 🚫 👷 🌌 🔬 🔛 &amp; 👆 ⚙️ ⚖ 🙃 📊-🕴 *➡ 🛠️ 🔢* ⏮️ ✅ `def` 🤪 🎭 📈 (🔃 1️⃣0️⃣0️⃣ 💓), 🙏 🗒 👈 **FastAPI** ⭐ 🔜 🔄. 👫 💼, ⚫️ 👻 ⚙️ `async def` 🚥 👆 *➡ 🛠️ 🔢* ⚙️ 📟 👈 🎭 🚧 <abbr title="Input/Output: disk reading or writing, network communications.">👤/🅾</abbr>.

, 👯‍♂️ ⚠, 🤞 👈 **FastAPI** 🔜 [⏩](index.md#_15){.internal-link target=_blank} 🌘 (⚖️ 🌘 ⭐) 👆 ⏮️ 🛠️.

### 🔗

    In many cases, OAuth2 with scopes can be an overkill.

    But if you know you need it, or you are curious, keep reading.

## OAuth2 scopes and OpenAPI

The OAuth2 specification defines "scopes" as a list of strings separated by spaces.

The content of each of these strings can have any format, but should not contain spaces.