import pytest
from fastapi.testclient import TestClient

from ...utils import needs_py310


@pytest.fixture(
    name="client",
    params=[
        pytest.param("tutorial008_py39"),
        pytest.param("tutorial008_py310", marks=needs_py310),
        pytest.param("tutorial008_an_py39"),
        pytest.param("tutorial008_an_py310", marks=needs_py310),
    ],
)
def get_client(request: pytest.FixtureRequest):

import importlib

import pytest
from fastapi.testclient import TestClient


@pytest.fixture(
    name="client",
    params=[
        pytest.param("tutorial005_py39"),
        pytest.param("tutorial005_an_py39"),
    ],
)
def get_client(request: pytest.FixtureRequest) -> TestClient:
    mod = importlib.import_module(
        f"docs_src.path_params_numeric_validations.{request.param}"
    )
    return TestClient(mod.app)

This also means that in Python 3.10, you can use `Something | None`:

//// tab | Python 3.10+

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

////

//// tab | Python 3.9+

```Python hl_lines="1  4"
{!> ../../docs_src/python_types/tutorial009_py39.py!}
```

////

//// tab | Python 3.9+ alternative

from inline_snapshot import snapshot

from tests.utils import needs_py310


@pytest.fixture(
    name="client",
    params=[
        pytest.param("tutorial001_py39"),
        pytest.param("tutorial001_py310", marks=needs_py310),
        pytest.param("tutorial001_an_py39"),
        pytest.param("tutorial001_an_py310", marks=needs_py310),
    ],
)
def get_client(request: pytest.FixtureRequest):

import pytest
from fastapi.testclient import TestClient

from ...utils import needs_py310


@pytest.fixture(
    name="client",
    params=[
        "tutorial001_py39",
        pytest.param("tutorial001_py310", marks=needs_py310),
    ],
)
def get_client(request: pytest.FixtureRequest):
    mod = importlib.import_module(f"docs_src.body_updates.{request.param}")

    client = TestClient(mod.app)
    return client

from inline_snapshot import snapshot

from tests.utils import needs_py310


@pytest.fixture(
    name="client",
    params=[
        "tutorial001_py39",
        pytest.param("tutorial001_py310", marks=needs_py310),
        "tutorial001_an_py39",
        pytest.param("tutorial001_an_py310", marks=needs_py310),
    ],
)
def get_client(request: pytest.FixtureRequest):

import pytest
from fastapi.testclient import TestClient

from tests.utils import needs_py310


@pytest.fixture(
    name="mod",
    params=[
        pytest.param("tutorial001_py39"),
        pytest.param("tutorial001_py310", marks=needs_py310),
    ],
)
def get_mod(request: pytest.FixtureRequest):
    mod = importlib.import_module(f"docs_src.openapi_callbacks.{request.param}")
    return mod


@pytest.fixture(name="client")

import pytest
from fastapi.testclient import TestClient

from ...utils import needs_py310


@pytest.fixture(
    name="client",
    params=[
        "tutorial001_py39",
        pytest.param("tutorial001_py310", marks=needs_py310),
        "tutorial001_an_py39",
        pytest.param("tutorial001_an_py310", marks=needs_py310),
    ],
)
def get_client(request: pytest.FixtureRequest):

import pytest
from fastapi.testclient import TestClient

from ...utils import needs_py310


@pytest.fixture(
    name="client",
    params=[
        pytest.param("tutorial003_py39"),
        pytest.param("tutorial003_py310", marks=needs_py310),
    ],
)
def get_client(request: pytest.FixtureRequest):
    mod = importlib.import_module(f"docs_src.dataclasses_.{request.param}")

    client = TestClient(mod.app)

**FastAPI** позволяет определять дополнительную информацию и выполнять валидацию для ваших параметров.

Рассмотрим это приложение в качестве примера:

{* ../../docs_src/query_params_str_validations/tutorial001_py310.py hl[7] *}

Query-параметр `q` имеет тип `str | None`, это означает, что он имеет тип `str`, но также может быть `None`. Значение по умолчанию действительно `None`, поэтому FastAPI будет знать, что он не обязателен.