from typing import Union

from fastapi import FastAPI
from pydantic.v1 import BaseModel


class Item(BaseModel):
    name: str
    description: Union[str, None] = None
    size: float


app = FastAPI()


@app.post("/items/")
async def create_item(item: Item) -> Item:

from typing import Annotated

from fastapi import FastAPI, Header

app = FastAPI()


@app.get("/items/")
async def read_items(
    strange_header: Annotated[str | None, Header(convert_underscores=False)] = None,
):

    "bar": {"id": "bar", "title": "Bar", "description": "The bartenders"},
}

app = FastAPI()


class Item(BaseModel):
    id: str
    title: str
    description: str | None = None


@app.get("/items/{item_id}", response_model=Item)
async def read_main(item_id: str, x_token: Annotated[str, Header()]):
    if x_token != fake_secret_token:

from typing import Annotated

from fastapi import FastAPI, Query

app = FastAPI()


@app.get("/items/")
async def read_items(
    q: Annotated[str | None, Query(min_length=3, max_length=50)] = None,
):
    results = {"items": [{"item_id": "Foo"}, {"item_id": "Bar"}]}
    if q:
        results.update({"q": q})

from typing import Annotated

from fastapi import FastAPI, Query

app = FastAPI()


@app.get("/items/")
async def read_items(q: Annotated[str | None, Query(alias="item-query")] = None):
    results = {"items": [{"item_id": "Foo"}, {"item_id": "Bar"}]}
    if q:
        results.update({"q": q})

from typing import Union

from fastapi import FastAPI, Query

app = FastAPI()


@app.get("/items/")
async def read_items(q: Union[str, None] = Query(default=None, alias="item-query")):
    results = {"items": [{"item_id": "Foo"}, {"item_id": "Bar"}]}
    if q:
        results.update({"q": q})

from typing import Annotated

from fastapi import FastAPI, Query

app = FastAPI()


@app.get("/items/")
async def read_items(
    q: Annotated[
        str | None, Query(min_length=3, max_length=50, pattern="^fixedquery$")
    ] = None,
):
    results = {"items": [{"item_id": "Foo"}, {"item_id": "Bar"}]}
    if q:
        results.update({"q": q})

from fastapi import FastAPI

app = FastAPI()


@app.get("/items/{item_id}")
async def read_user_item(
    item_id: str, needy: str, skip: int = 0, limit: int | None = None
):
    item = {"item_id": item_id, "needy": needy, "skip": skip, "limit": limit}

    summary: Optional[str] = None,
    description: Optional[str] = None,
    routes: Sequence[BaseRoute],
    webhooks: Optional[Sequence[BaseRoute]] = None,
    tags: Optional[list[dict[str, Any]]] = None,
    servers: Optional[list[dict[str, Union[str, Any]]]] = None,
    terms_of_service: Optional[str] = None,
    contact: Optional[dict[str, Union[str, Any]]] = None,

| <<<pom>>>             |               | <= type>   | none      |                       |                       |
*-----------------------+---------------+------------+-----------+-----------------------+-----------------------+
| <<<bom>>> *           |               | <<<pom>>>  | none      |                       |                       |