from fastapi import FastAPI
from pydantic_settings import BaseSettings


class Settings(BaseSettings):
    openapi_url: str = "/openapi.json"


settings = Settings()

app = FastAPI(openapi_url=settings.openapi_url)


@app.get("/")
def root():

Например, если у вас есть функция:

```Python
@lru_cache
def say_hi(name: str, salutation: str = "Ms."):
    return f"Hello {salutation} {name}"
```

ваша программа может выполняться так:

```mermaid
sequenceDiagram

participant code as Code
participant function as say_hi()

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

app = FastAPI()


class Items(BaseModel):
    items: dict[str, int]


@app.post("/foo")
def foo(items: Items):
    return items.items


client = TestClient(app)


def test_additional_properties_post():
    response = client.post("/foo", json={"items": {"foo": 1, "bar": 2}})

items = {}


@app.on_event("startup")
async def startup_event():
    items["foo"] = {"name": "Fighters"}
    items["bar"] = {"name": "Tenders"}


@app.get("/items/{item_id}")
async def read_items(item_id: str):

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

app = FastAPI()

oauth2_scheme = OAuth2PasswordBearer(tokenUrl="token")


@app.get("/items/")
async def read_items(token: Annotated[str, Depends(oauth2_scheme)]):

        fmt = req.getParameter("fmt");
        if (fmt == null) {
            fmt = "col";
        }
        sort = 0;
        if ((str = req.getParameter("sort")) == null || str.equals("name")) {
            sort = 0;
        } else if (str != null) {
            switch (str) {
            case "size":
                sort = 1;
                break;
            case "type":
                sort = 2;

from typing import Union

from fastapi import FastAPI, Query

app = FastAPI()


@app.get("/items/")
async def read_items(
    hidden_query: Union[str, None] = Query(default=None, include_in_schema=False),
):
    if hidden_query:
        return {"hidden_query": hidden_query}
    else:

from fastapi import FastAPI, Query

app = FastAPI()


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

async def add_process_time_header(request: Request, call_next):
    start_time = time.perf_counter()
    response = await call_next(request)
    process_time = time.perf_counter() - start_time
    response.headers["X-Process-Time"] = str(process_time)

from fastapi import FastAPI
from fastapi.testclient import TestClient

app = FastAPI()


@app.put("/items/{item_id}")
def save_item_no_body(item_id: str):
    return {"item_id": item_id}


client = TestClient(app)


def test_put_no_body():
    response = client.put("/items/foo")
    assert response.status_code == 200, response.text
    assert response.json() == {"item_id": "foo"}


def test_put_no_body_with_body():