assert response.json() == {
        "detail": [
            {
                "type": "missing",
                "loc": ["query", "p"],
                "msg": "Field required",
                "input": IsOneOf(None, {}),
            }
        ]
    }


@pytest.mark.parametrize(
    "path",
    ["/required-list-str", "/model-required-list-str"],
)
def test_required_list_str(path: str):
    client = TestClient(app)

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

from fastapi.testclient import TestClient
from inline_snapshot import snapshot
from pydantic import BaseModel, HttpUrl

app = FastAPI()


class Invoice(BaseModel):
    id: str
    title: str | None = None
    customer: str
    total: float


class InvoiceEvent(BaseModel):
    description: str
    paid: bool


class InvoiceEventReceived(BaseModel):
    ok: bool

// along with this program.  If not, see <http://www.gnu.org/licenses/>.

package csv

import (
	"encoding/xml"
	"errors"
	"fmt"
	"io"
	"strings"
	"unicode/utf8"
)

const (
	none   = "none"
	use    = "use"
	ignore = "ignore"

	defaultRecordDelimiter      = "\n"
	defaultFieldDelimiter       = ","
	defaultQuoteCharacter       = `"`
	defaultQuoteEscapeCharacter = `"`

from fastapi import FastAPI
from fastapi.openapi.docs import (
    get_redoc_html,
    get_swagger_ui_html,
    get_swagger_ui_oauth2_redirect_html,
)

app = FastAPI(docs_url=None, redoc_url=None)


@app.get("/docs", include_in_schema=False)
async def custom_swagger_ui_html():
    return get_swagger_ui_html(
        openapi_url=app.openapi_url,
        title=app.title + " - Swagger UI",

from fastapi.testclient import TestClient

app = FastAPI()


@app.get("/query")
def read_query(q: str | None):
    return q


@app.get("/explicit-query")
def read_explicit_query(q: str | None = Query()):
    return q


@app.post("/body-embed")
def send_body_embed(b: str | None = Body(embed=True)):
    return b


client = TestClient(app)


def test_required_nonable_query_invalid():

Это означает, что `item` может быть `int` или `str`.

#### Возможно `None` { #possibly-none }

Вы можете объявить, что значение может иметь определённый тип, например `str`, но также может быть и `None`.

//// tab | Python 3.10+

```Python hl_lines="1"
{!> ../../docs_src/python_types/tutorial009_py310.py!}
```

////

public interface Location {

    /**
     * Return the line number where the current event ends,
     * returns -1 if none is available.
     * @return the current line number
     */
    int getLineNumber();

    /**
     * Return the column number where the current event ends,
     * returns -1 if none is available.
     * @return the current column number
     */
    int getColumnNumber();

    /**

## Optionale Parameter { #optional-parameters }

Auf die gleiche Weise können Sie optionale Query-Parameter deklarieren, indem Sie deren Defaultwert auf `None` setzen:

{* ../../docs_src/query_params/tutorial002_py310.py hl[7] *}

In diesem Fall wird der Funktionsparameter `q` optional und standardmäßig `None` sein.

/// check | Testen

from typing import Annotated

from fastapi import FastAPI, Query

app = FastAPI()


@app.get("/items/")
async def read_items(q: Annotated[list[str] | None, Query()] = None):
    query_items = {"q": q}