[
        ("/items", None, 200, {"strange_header": None}),
        ("/items", {"X-Header": "notvalid"}, 200, {"strange_header": None}),
        (
            "/items",
            {"strange_header": "FastAPI test"},
            200,
            {"strange_header": "FastAPI test"},
        ),
        (
            "/items",
            {"strange-header": "Not really underscore"},

from fastapi import FastAPI, Query

app = FastAPI()


@app.get("/items/")
async def read_items(
    q: Annotated[
        str | None,
        Query(
            title="Query string",
            description="Query string for the items to search in the database that have a good match",
            min_length=3,
        ),
    ] = None,
):
    results = {"items": [{"item_id": "Foo"}, {"item_id": "Bar"}]}
    if q:

```Python hl_lines="6-7"
{!../../docs_src/path_params/tutorial001.py!}
```

💲 ➡ 🔢 `item_id` 🔜 🚶‍♀️ 👆 🔢 ❌ `item_id`.

, 🚥 👆 🏃 👉 🖼 &amp; 🚶 <a href="http://127.0.0.1:8000/items/foo" class="external-link" target="_blank">http://127.0.0.1:8000/items/foo</a>, 👆 🔜 👀 📨:

```JSON
{"item_id":"foo"}
```

## ➡ 🔢 ⏮️ 🆎

👆 💪 📣 🆎 ➡ 🔢 🔢, ⚙️ 🐩 🐍 🆎 ✍:

```Python hl_lines="7"

    String simple = "a,b,c,d";
    Iterable<String> items = COMMA_SPLITTER.limit(1).split(simple);
    assertThat(items).containsExactly("a,b,c,d").inOrder();
  }

  public void testLimitSeparator() {
    String simple = "a,b,c,d";
    Iterable<String> items = COMMA_SPLITTER.limit(2).split(simple);
    assertThat(items).containsExactly("a", "b,c,d").inOrder();
  }

constraints.Future.message      = {item} must be in the future.
constraints.Max.message         = {item} must be less than or equal to {value}.
constraints.Min.message         = {item} must be greater than or equal to {value}.
constraints.NotNull.message     = {item} may not be null.
constraints.Null.message        = {item} must be null.
constraints.Past.message        = {item} must be in the past.
constraints.Pattern.message     = {item} must match "{regexp}".

constraints.Future.message      = {item} must be in the future.
constraints.Max.message         = {item} must be less than or equal to {value}.
constraints.Min.message         = {item} must be greater than or equal to {value}.
constraints.NotNull.message     = {item} may not be null.
constraints.Null.message        = {item} must be null.
constraints.Past.message        = {item} must be in the past.
constraints.Pattern.message     = {item} must match "{regexp}".

from fastapi import FastAPI

app = FastAPI()


@app.get("/items/", tags=["items"])
async def read_items():
    return [{"name": "Foo", "price": 42}]


@app.get("/users/", tags=["users"])
async def read_users():
    return [{"username": "johndoe"}]


@app.get("/elements/", tags=["items"], deprecated=True)
async def read_elements():

client = TestClient(app)


def test_no_token():
    response = client.get("/items")
    assert response.status_code == 401, response.text
    assert response.json() == {"detail": "Not authenticated"}
    assert response.headers["WWW-Authenticate"] == "Bearer"


def test_token():
    response = client.get("/items", headers={"Authorization": "Bearer testtoken"})
    assert response.status_code == 200, response.text

            },
        ),
        (
            "/items?q=foo&skip=1",
            200,
            {"items": [{"item_name": "Bar"}, {"item_name": "Baz"}], "q": "foo"},
        ),
        (
            "/items?q=bar&limit=2",
            200,
            {"items": [{"item_name": "Foo"}, {"item_name": "Bar"}], "q": "bar"},
        ),
        (
            "/items?q=bar&skip=1&limit=1",
            200,

        "paths": {
            "/items/": {
                "get": {
                    "responses": {
                        "200": {
                            "description": "Successful Response",
                            "content": {"application/json": {"schema": {}}},
                        }
                    },
                    "summary": "Read Items",