That's it.

**2 lines**.

And it has the same shape and structure that all your *path operation functions* have.

You can think of it as a *path operation function* without the "decorator" (without the `@app.get("/some-path")`).

And it can return anything you want.

In this case, this dependency expects:

* An optional query parameter `q` that is a `str`.

 * one or more methods to modify the behavior of the backing multiset as desired per the <a
 * href="http://en.wikipedia.org/wiki/Decorator_pattern">decorator pattern</a>.
 *
 * <p><b>Warning:</b> The methods of {@code ForwardingMultiset} forward <b>indiscriminately</b> to
 * the methods of the delegate. For example, overriding {@link #add(Object, int)} alone <b>will

 * override one or more methods to modify the behavior of the backing set as desired per the <a
 * href="http://en.wikipedia.org/wiki/Decorator_pattern">decorator pattern</a>.
 *
 * <p><b>Warning:</b> The methods of {@code ForwardingNavigableSet} forward <i>indiscriminately</i>
 * to the methods of the delegate. For example, overriding {@link #add} alone <i>will not</i> change

 * should override one or more methods to modify the behavior of the backing multiset as desired per
 * the <a href="http://en.wikipedia.org/wiki/Decorator_pattern">decorator pattern</a>.
 *
 * <p><b>Warning:</b> The methods of {@code ForwardingSortedMultiset} forward
 * <b>indiscriminately</b> to the methods of the delegate. For example, overriding {@link

compilation to JavaScript, it cannot rely on the types to define validation, serialization and documentation at the same time. Due to this and some design decisions, to get validation, serialization and automatic schema generation, it's needed to add decorators in many places. So, it becomes quite verbose.

It can't handle nested models very well. So, if the JSON body in the request is a JSON object that has inner fields that in turn are nested JSON objects, it cannot be properly documented and...

 * override one or more methods to modify the behavior of the backing set as desired per the <a
 * href="http://en.wikipedia.org/wiki/Decorator_pattern">decorator pattern</a>.
 *
 * <p><b>Warning:</b> The methods of {@code ForwardingNavigableSet} forward <i>indiscriminately</i>
 * to the methods of the delegate. For example, overriding {@link #add} alone <i>will not</i> change

```Python
def get_settings():
    return Settings()
```

würden wir dieses Objekt für jeden Request erstellen und die `.env`-Datei für jeden Request lesen. ⚠️

Da wir jedoch den `@lru_cache`-Dekorator oben verwenden, wird das `Settings`-Objekt nur einmal erstellt, nämlich beim ersten Aufruf. ✔️

{* ../../docs_src/settings/app03_an_py39/main.py hl[1,11] *}

    * Pydantic, JSON objen ne kadar derin (nested) olursa olsun doğrulamasını ve gösterimini yapıyor
* **Genişletilebilir**:
    * Pydantic özelleştirilmiş data tiplerinin tanımlanmasının yapılmasına izin veriyor ayrıca validator decoratorü ile senin doğrulamaları genişletip, kendi doğrulayıcılarını yazmana izin veriyor.

* **Renouvelable**:
    * Pydantic permet de définir de nouveaux types de données ou vous pouvez étendre la validation avec des méthodes sur un modèle décoré avec le<abbr title="en anglais: validator decorator"> décorateur de validation</abbr>

    * Bạn có thể có các object **JSON lồng nhau** và tất cả chúng đã validate và annotated.
* **Có khả năng mở rộng**:
    * Pydantic cho phép bạn tùy chỉnh kiểu dữ liệu bằng việc định nghĩa hoặc bạn có thể mở rộng validation với các decorator trong model.