version="0.0.1",
    terms_of_service="http://example.com/terms/",
    contact={
        "name": "Deadpoolio the Amazing",
        "url": "http://x-force.example.com/contact/",
        "email": "dp@x-force.example.com",
    },
    license_info={
        "name": "Apache 2.0",
        "url": "https://www.apache.org/licenses/LICENSE-2.0.html",
    },
)


@app.get("/items/")

    version="0.0.1",
    terms_of_service="http://example.com/terms/",
    contact={
        "name": "Deadpoolio the Amazing",
        "url": "http://x-force.example.com/contact/",
        "email": "dp@x-force.example.com",
    },
    license_info={
        "name": "Apache 2.0",
        "identifier": "MIT",
    },
)


@app.get("/items/")
async def read_items():

            "termsOfService": "http://example.com/terms/",
            "contact": {
                "name": "Deadpoolio the Amazing",
                "url": "http://x-force.example.com/contact/",
                "email": "dp@x-force.example.com",
            },
            "license": {
                "name": "Apache 2.0",
                "url": "https://www.apache.org/licenses/LICENSE-2.0.html",
            },

    yaml_data = """
        name: Deadpoolio
        tags:
        - x-force
        - x-men
        - x-avengers
        """
    response = client.post("/items/", content=yaml_data)
    assert response.status_code == 200, response.text
    assert response.json() == {
        "name": "Deadpoolio",
        "tags": ["x-force", "x-men", "x-avengers"],
    }


@needs_pydanticv1

    yaml_data = """
        name: Deadpoolio
        tags:
        - x-force
        - x-men
        - x-avengers
        """
    response = client.post("/items/", content=yaml_data)
    assert response.status_code == 200, response.text
    assert response.json() == {
        "name": "Deadpoolio",
        "tags": ["x-force", "x-men", "x-avengers"],
    }


@needs_pydanticv2

            "termsOfService": "http://example.com/terms/",
            "contact": {
                "name": "Deadpoolio the Amazing",
                "url": "http://x-force.example.com/contact/",
                "email": "dp@x-force.example.com",
            },
            "license": {
                "name": "Apache 2.0",
                "identifier": "MIT",
            },
            "version": "0.0.1",
        },

C'est pourquoi il est logique d'utiliser du code asynchrone ⏸🔀⏯ pour des APIs web.

Ce type d'asynchronicité est ce qui a rendu NodeJS populaire (bien que NodeJS ne soit pas parallèle) et c'est la force du Go en tant que langage de programmation.

Et c'est le même niveau de performance que celui obtenu avec **FastAPI**.

This will let **FastAPI** know that this parameter is required.

### Required with `None`

You can declare that a parameter can accept `None`, but that it's still required. This would force clients to send a value, even if the value is `None`.

To do that, you can declare that `None` is a valid type but still use `...` as the default:

=== "Python 3.10+"

    ```Python hl_lines="9"

                ```python
                app = FastAPI(
                    contact={
                        "name": "Deadpoolio the Amazing",
                        "url": "http://x-force.example.com/contact/",
                        "email": "dp@x-force.example.com",
                    }
                )
                ```
                """
            ),
        ] = None,
        license_info: Annotated[