}

    /**
     * Test all fields are public and accessible
     */
    @Test
    @DisplayName("Test all fields are public")
    public void testAllFieldsArePublic() {
        // Get all declared fields
        Field[] fields = ServerData.class.getDeclaredFields();

        // Verify we have the expected number of fields
        assertEquals(19, fields.length);

        // Verify all fields are public

Normalmente são usados para declarar permissões de segurança específicas, por exemplo:

* `users:read` ou `users:write` são exemplos comuns.
* `instagram_basic` é usado pelo Facebook e Instagram.
* `https://www.googleapis.com/auth/drive` é usado pelo Google.

/// info | Informação

No OAuth2, um "scope" é apenas uma string que declara uma permissão específica necessária.

///

Este parámetro no crea ese endpoint / *path operation*, pero declara que la URL `/token` será la que el cliente deberá usar para obtener el token. Esa información se usa en OpenAPI, y luego en los sistemas de documentación interactiva del API.

Pronto también crearemos la verdadera *path operation*.

            assertNotNull(e.getCause());
            assertTrue(e.getCause() instanceof IllegalArgumentException);
        }
    }

    /**
     * Test exception in method that declares throws
     */
    public void test_exceptionInMethod() {
        try {
            methodThatThrowsException();
            fail("Should have thrown CrawlerSystemException");

If you go to `/docs`, you will see that it has the **schemas** for the data to be sent in requests and received in responses:

<img src="/img/tutorial/generate-clients/image01.png">

You can see those schemas because they were declared with the models in the app.

That information is available in the app's **OpenAPI schema**, and then shown in the API docs.

But if you return a `Response` directly (or any subclass, like `JSONResponse`), the data won't be automatically converted (even if you declare a `response_model`), and the documentation won't be automatically generated (for example, including the specific "media type", in the HTTP header `Content-Type` as part of the generated OpenAPI).

Escribes Python estándar con tipos:

```Python
from datetime import date

from pydantic import BaseModel

# Declara una variable como un str
# y obtiene soporte del editor dentro de la función
def main(user_id: str):
    return user_id


# Un modelo de Pydantic
class User(BaseModel):
    id: int
    name: str

Vous écrivez du python standard avec des annotations de types:

```Python
from datetime import date

from pydantic import BaseModel

# Déclare une variable comme étant une str
# et profitez de l'aide de votre IDE dans cette fonction
def main(user_id: str):
    return user_id


# Un modèle Pydantic
class User(BaseModel):
    id: int
    name: str

///

### Crear el objeto `Settings`

Importa `BaseSettings` de Pydantic y crea una sub-clase, muy similar a un modelo de Pydantic.

De la misma forma que con los modelos de Pydantic, declaras atributos de clase con anotaciones de tipos, y posiblemente, valores por defecto.

Next it will convert and validate the data. So, when you use that `settings` object, you will have data of the types you declared (e.g. `items_per_user` will be an `int`).

### Use the `settings` { #use-the-settings }

Then you can use the new `settings` object in your application:

{* ../../docs_src/settings/tutorial001.py hl[18:20] *}