"title": "Strange Header",
                                }
                            )
                            | IsDict(
                                # TODO: remove when deprecating Pydantic v1
                                {"title": "Strange Header", "type": "string"}
                            ),
                            "name": "strange_header",
                            "in": "header",

                                    "title": "Q",
                                }
                            )
                            | IsDict(
                                # TODO: remove when deprecating Pydantic v1
                                {
                                    "title": "Q",
                                    "type": "array",
                                    "items": {"type": "string"},

from typing import Any

from fastapi import FastAPI
from fastapi.testclient import TestClient
from pydantic import BaseModel, ConfigDict

from .utils import needs_pydanticv1, needs_pydanticv2


@needs_pydanticv2
def test_read_with_orm_mode() -> None:
    class PersonBase(BaseModel):
        name: str
        lastname: str

    class Person(PersonBase):
        @property
        def full_name(self) -> str:

👉 🍕 📶 😐, 🌅 📟 🎲 ⏪ 😰 👆:

```Python hl_lines="9-13  36-53"
{!../../docs_src/openapi_callbacks/tutorial001.py!}
```

/// tip

`callback_url` 🔢 🔢 ⚙️ Pydantic <a href="https://docs.pydantic.dev/latest/concepts/types/#urls" class="external-link" target="_blank">📛</a> 🆎.

///

🕴 🆕 👜 `callbacks=messages_callback_router.routes` ❌ *➡ 🛠️ 👨‍🎨*. 👥 🔜 👀 ⚫️❔ 👈 ⏭.

## 🔬 ⏲

repository-code: 'https://github.com/fastapi/fastapi'
url: 'https://fastapi.tiangolo.com'
abstract: >-
  FastAPI framework, high performance, easy to learn, fast to code,
  ready for production
keywords:
  - fastapi
  - pydantic
  - starlette

from typing import Annotated

from fastapi import Depends, FastAPI
from fastapi.security import OAuth2PasswordBearer
from pydantic import BaseModel

app = FastAPI()

oauth2_scheme = OAuth2PasswordBearer(tokenUrl="token")


class User(BaseModel):
    username: str
    email: str | None = None
    full_name: str | None = None
    disabled: bool | None = None


def fake_decode_token(token):
    return User(

👈 🌌 👤 💪 🔎 🏆 🌌 📉 📟 ❎ 🌅 💪, ✔️ 🛠️ 🌐, 🆎 & ❌ ✅, ♒️.

🌐 🌌 👈 🚚 🏆 🛠️ 💡 🌐 👩‍💻.

## 📄

⏮️ 🔬 📚 🎛, 👤 💭 👈 👤 🔜 ⚙️ <a href="https://docs.pydantic.dev/" class="external-link" target="_blank">**Pydantic**</a> 🚮 📈.

⤴️ 👤 📉 ⚫️, ⚒ ⚫️ 🍕 🛠️ ⏮️ 🎻 🔗, 🐕‍🦺 🎏 🌌 🔬 ⚛ 📄, &amp; 📉 👨‍🎨 🐕‍🦺 (🆎 ✅, ✍) ⚓️ 🔛 💯 📚 👨‍🎨.

                    "msg": "Field required",
                    "input": None,
                },
            ]
        }
    ) | IsDict(
        # TODO: remove when deprecating Pydantic v1
        {
            "detail": [
                {
                    "loc": ["header", "x-token"],
                    "msg": "field required",
                    "type": "value_error.missing",

from typing import Union

from fastapi import Depends, FastAPI
from fastapi.security import OAuth2PasswordBearer
from pydantic import BaseModel

app = FastAPI()

oauth2_scheme = OAuth2PasswordBearer(tokenUrl="token")


class User(BaseModel):
    username: str
    email: Union[str, None] = None
    full_name: Union[str, None] = None
    disabled: Union[bool, None] = None


def fake_decode_token(token):
    return User(

from fastapi import FastAPI
from pydantic import BaseModel

app = FastAPI()


class Item(BaseModel):
    name: str
    description: str | None = None
    price: float
    tax: float | None = None
    tags: set[str] = set()


@app.post("/items/", response_model=Item, summary="Create an item")
async def create_item(item: Item):
    """
    Create an item with all the information:

    - **name**: each item must have a name