@router.route("/items/")
def read_items(request: Request):
    return JSONResponse({"hello": "world"})


app.include_router(router)

client = TestClient(app)


def test_sub_router():
    response = client.get("/items/")
    assert response.status_code == 200, response.text

Wenn Sie keinen spezifischen Wert haben wollen, sondern der Parameter einfach optional sein soll, dann setzen Sie den Defaultwert auf `None`.

Aber wenn Sie wollen, dass ein Query-Parameter erforderlich ist, vergeben Sie einfach keinen Defaultwert:

{* ../../docs_src/query_params/tutorial005_py39.py hl[6:7] *}

   *
   * <p>Historically, {@code Function} instances in this library have implemented this method to
   * recognize certain cases where distinct {@code Function} instances would in fact behave
   * identically. However, as code migrates to {@code java.util.function}, that behavior will
   * disappear. It is best not to depend on it.
   */
  @Override
  boolean equals(@Nullable Object obj);

/**
 * A TimeLimiter implementation which actually does not attempt to limit time at all. This may be
 * desirable to use in some unit tests. More importantly, attempting to debug a call which is
 * time-limited would be extremely annoying, so this gives you a time-limiter you can easily swap in
 * for your real time-limiter while you're debugging.
 *
 * @author Kevin Bourrillion
 * @author Jens Nyman
 * @since 1.0
 */

// before issuing IO to underlying devices. ZFS users often enable features like
// compression and checksumming which currently necessitates mutating data in
// the kernel.
//
// DirectIO semantics for a filesystem like ZFS would be quite different than
// the semantics on filesystems like XFS, and these semantics are not
// implemented at this time.
// For more information on why typical DirectIO semantics do not apply to ZFS

            from(src) {
                eachFile {
                    // Remove top folder when unzipping, that way we get rid of Android Studio.app folder that can cause issues on Mac
                    // where MacOS would kill the Android Studio process right after start, issue: https://github.com/gradle/gradle-profiler/issues/469
                    @Suppress("SpreadOperator")

    // TODO this is only to provide a project for plugins that don't need a project to execute but need some
    // of the values from a MavenProject. Ideally this should be something internal and nothing outside Maven
    // would ever need this so it should not be exposed in a public API
    MavenProject buildStandaloneSuperProject(ProjectBuilderConfiguration configuration) throws ProjectBuildingException;

```txt
Hello, World from Flask!
```

并且如果您访问 <a href="http://localhost:8000/v2" class="external-link" target="_blank">http://localhost:8000/v2</a>，您将会看到由 FastAPI 返回的响应：

```JSON
{
    "message": "Hello World"
}

     * @param request The model building request that holds the parameters, must not be {@code null}.
     * @return The result of the model building, never {@code null}.
     * @throws ModelBuildingException If the effective model could not be built.
     */
    ModelBuildingResult build(ModelBuildingRequest request) throws ModelBuildingException;

    /**

* fixes a validation error that could prevent updates to StatefulSet objects containing non-normalized resource requests ([#66165](https://github.com/kubernetes/kubernetes/pull/66165), [@liggitt](https://github.com/liggitt))