///

Ce qui signifie : "la variable `items` est une `list`, et chacun de ses éléments a pour type `str`.

En faisant cela, votre éditeur pourra vous aider, même pendant que vous traitez des éléments de la liste.

<img src="/img/python-types/image05.png">

Sans types, c'est presque impossible à réaliser.

Vous remarquerez que la variable `item` n'est qu'un des éléments de la list `items`.

Если клиент запросит `http://example.com/items/foo` (`item_id` `"foo"`), то он получит статус-код 200 и ответ в формате JSON:

```JSON
{
  "item": "The Foo Wrestlers"
}
```

Но если клиент запросит `http://example.com/items/bar` (несуществующий `item_id` `"bar"`), то он получит статус-код 404 (ошибка "не найдено") и JSON-ответ в виде:

```JSON
{
  "detail": "Item not found"
}
```

/// tip | "Подсказка"

from fastapi import FastAPI

app = FastAPI()


@app.get("/items/", operation_id="some_specific_id_you_define")
async def read_items():

from fastapi import FastAPI

app = FastAPI()


@app.get("/items/", openapi_extra={"x-aperture-labs-portal": "blue"})
async def read_items():

///

## Metadaten deklarieren

Sie können die gleichen Parameter deklarieren wie für `Query`.

Um zum Beispiel einen `title`-Metadaten-Wert für den Pfad-Parameter `item_id` zu deklarieren, schreiben Sie:

//// tab | Python 3.10+

```Python hl_lines="10"
{!> ../../docs_src/path_params_numeric_validations/tutorial001_an_py310.py!}
```

////

//// tab | Python 3.9+

        "openapi": "3.1.0",
        "info": {"title": "FastAPI", "version": "0.1.0"},
        "paths": {
            "/items/{item_id}": {
                "get": {
                    "responses": {
                        "404": {
                            "description": "The item was not found",
                            "content": {
                                "application/json": {

## FastAPI App with Tags

In many cases your FastAPI app will be bigger, and you will probably use tags to separate different groups of *path operations*.

For example, you could have a section for **items** and another section for **users**, and they could be separated by tags:

//// tab | Python 3.9+

```Python hl_lines="21  26  34"
{!> ../../docs_src/generate_clients/tutorial002_py39.py!}
```

////

{
  "item": "The Foo Wrestlers"
}
```

Mas se o cliente faz uma requisição para `http://example.com/items/bar` (ou seja, um não existente `item_id "bar"`), esse cliente receberá um HTTP status code 404 (o erro "não encontrado" — *not found error*), e uma resposta JSON:

```JSON
{
  "detail": "Item not found"
}
```

/// tip | "Dica"

    return client


@needs_py39
@pytest.mark.parametrize(
    "url,data",
    [
        ("/items/foo", {"name": "Foo", "price": 50.2}),
        (
            "/items/bar",
            {"name": "Bar", "description": "The bartenders", "price": 62, "tax": 20.2},
        ),
        (
            "/items/baz",
            {
                "name": "Baz",
                "description": None,

from fastapi import FastAPI

app = FastAPI()


@app.get("/items/", include_in_schema=False)
async def read_items():