The `Union[str, None]` part allows your editor to provide better support, but it is not what tells FastAPI that this parameter is not required.

Then, we can pass more parameters to `Query`. In this case, the `max_length` parameter that applies to strings:

```Python
q: Union[str, None] = Query(default=None, max_length=50)
```

- [`KT-55375`](https://youtrack.jetbrains.com/issue/KT-55375) Remove "legacy" mode of jvm-abi-gen plugin
- [`KT-53470`](https://youtrack.jetbrains.com/issue/KT-53470) FIR: pass `MemberGenerationContext` to all methods of FirDeclarationGenerationExtension
- [`KT-51092`](https://youtrack.jetbrains.com/issue/KT-51092) Lombok `@Value` causes IllegalAccessError

   * This avoids sending potentially sensitive data like HTTP cookies to the proxy unencrypted.
   *
   * In order to support preemptive authentication we pass a fake "Auth Failed" response to the
   * authenticator. This gives the authenticator the option to customize the CONNECT request. It can
   * decline to do so by returning null, in which case OkHttp will use it as-is.
   */

  http://www.eclipse.org/org/documents/edl-v10.php.

For an explanation of what dual-licensing means to you, see:
https://www.eclipse.org/legal/eplfaq.php#DUALLIC

****
The epl-2.0 is copied below in order to pass the pkg.go.dev license check (https://pkg.go.dev/license-policy).
****
Eclipse Public License - v 2.0

    THE ACCOMPANYING PROGRAM IS PROVIDED UNDER THE TERMS OF THIS ECLIPSE

```Python hl_lines="17-19  22-23  29-33"
{!../../../docs_src/openapi_callbacks/tutorial001.py!}
```

回调*路径操作*与常规*路径操作*有两点主要区别：

* 它不需要任何实际的代码，因为应用不会调用这段代码。它只是用于存档*外部 API*。因此，函数的内容只需要 `pass` 就可以了
* *路径*可以包含 <a href="https://github.com/OAI/OpenAPI-Specification/blob/master/versions/3.0.2.md#key-expression" class="external-link" target="_blank">OpenAPI 3 表达式</a>（详见下文），可以使用带参数的变量，以及发送至您的 API 的原始请求的部分

### 回调路径表达式

of uniqueness over space and time and are computationally difficult to guess. They are globally unique identifiers which can be locally generated without contacting a global registration authority. UUIDs are intended as unique identifiers for both mass tagging objects with an extremely short lifetime and to reliably identifying very persistent objects across a network.

When you PUT an object in a versioning-enabled bucket, the noncurrent version is not overwritten. The following figure shows...

To declare types that have type parameters (internal types), like `list`, `dict`, `tuple`:

* If you are in a Python version lower than 3.9, import their equivalent version from the `typing` module
* Pass the internal type(s) as "type parameters" using square brackets: `[` and `]`

In Python 3.9 it would be:

```Python
my_list: list[str]
```

In versions of Python before 3.9, it would be:

```Python

### Tests

* Help me check that the PR has **tests**.

* Check that the tests **fail** before the PR. 🚨

* Then check that the tests **pass** after the PR. ✅

* Many PRs don't have tests, you can **remind** them to add tests, or you can even **suggest** some tests yourself. That's one of the things that consume most time and you can help a lot with that.

    *   Add TensorSpec to represent the specification of Tensors.
    *   Constant folding pass is now deterministic.
    *   Support `float16` `dtype` in `tf.linalg.*`.
    *   Add `tf.estimator.export.TensorServingInputReceiver` that allows
        `tf.estimator.Estimator.export_savedmodel` to pass raw tensors to model
        functions.

## Deprecations

- E2e.test: removed the  `--viper-config` flag. If you were previously using this to pass flags to `e2e.test` via a file, you will need to pass them directly on the command line, e.g. `e2e.test --e2e-output-dir`. ([#102598](https://github.com/kubernetes/kubernetes/pull/102598), [@dims](https://github.com/dims))