import pytest
from fastapi import FastAPI
from fastapi.testclient import TestClient

app = FastAPI()


@app.get("/a", responses={"hello": {"description": "Not a valid additional response"}})
async def a():
    pass  # pragma: no cover


openapi_schema = {
    "openapi": "3.1.0",
    "info": {"title": "FastAPI", "version": "0.1.0"},
    "paths": {
        "/a": {
            "get": {
                "responses": {

from fastapi import FastAPI
from fastapi.responses import UJSONResponse

app = FastAPI()


@app.get("/items/", response_class=UJSONResponse)
async def read_items():

from fastapi import FastAPI
from fastapi.responses import ORJSONResponse

app = FastAPI(default_response_class=ORJSONResponse)


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

import pytest
from fastapi import Body, FastAPI, Query
from fastapi.testclient import TestClient
from typing_extensions import Annotated

app = FastAPI()


@app.post("/")
async def get(
    x: Annotated[float, Query(allow_inf_nan=True)] = 0,
    y: Annotated[float, Query(allow_inf_nan=False)] = 0,
    z: Annotated[float, Query()] = 0,
    b: Annotated[float, Body(allow_inf_nan=False)] = 0,
) -> str:
    return "OK"

from typing import Any

from fastapi import FastAPI, Response
from fastapi.testclient import TestClient

app = FastAPI()


@app.delete(
    "/{id}",
    status_code=204,
    response_model=None,
)
async def delete_deployment(
    id: int,
    response: Response,
) -> Any:
    response.status_code = 400
    return {"msg": "Status overwritten", "id": id}


client = TestClient(app)

app = FastAPI()

oauth2_scheme = OAuth2PasswordBearer(
    tokenUrl="/token",
    description="OAuth2PasswordBearer security scheme",
    auto_error=False,
)


@app.get("/items/")
async def read_items(token: Optional[str] = Security(oauth2_scheme)):
    if token is None:
        return {"msg": "Create an account first"}
    return {"token": token}


client = TestClient(app)

from fastapi import FastAPI
from fastapi.responses import ORJSONResponse

app = FastAPI()


@app.get("/items/", response_class=ORJSONResponse)
async def read_items():

    media_type = "application/x-level-5"


async def dep0(response: Response):
    response.headers["x-level0"] = "True"


async def dep1(response: Response):
    response.headers["x-level1"] = "True"


async def dep2(response: Response):
    response.headers["x-level2"] = "True"


async def dep3(response: Response):
    response.headers["x-level3"] = "True"


async def dep4(response: Response):

from fastapi import FastAPI
from fastapi.middleware.httpsredirect import HTTPSRedirectMiddleware

app = FastAPI()

app.add_middleware(HTTPSRedirectMiddleware)


@app.get("/")
async def main():

Это совершенно обычная функция, которая может принимать параметры.

Она может быть как асинхронной `async def`, так и обычной `def` функцией, **FastAPI** знает, как правильно ее выполнить.

В нашем примере фоновая задача будет вести запись в файл (симулируя отправку письма).

Так как операция записи не использует `async` и `await`, мы определим ее как обычную `def`:

```Python hl_lines="6-9"