Headers.Builder().add("héader1", "value1")
    }.also { expected ->
      assertThat(expected.message)
        .isEqualTo("Unexpected char 0xe9 at 1 in header name: héader1")
    }
  }

  @Test fun builderRejectsUnicodeInHeaderValue() {
    assertFailsWith<IllegalArgumentException> {
      Headers.Builder().add("header1", "valué1")
    }.also { expected ->
      assertThat(expected.message)

{* ../../docs_src/path_params/tutorial002.py hl[7] *}

In diesem Fall wird `item_id` als `int` deklariert, also als Ganzzahl.

/// check

Dadurch erhalten Sie Editor-Unterstützung innerhalb Ihrer Funktion, mit Fehlerprüfungen, Codevervollständigung, usw.

///

## Daten-<abbr title="Auch bekannt als: Serialisierung, Parsen, Marshalling">Konversion</abbr>

      clientReader.processNextFrame()
    }.also { expected ->
      assertThat(expected.message)
        .isEqualTo("Control frames must be final.")
    }
  }

  @Test fun reservedFlag1IsUnsupportedWithNoCompression() {
    data.write("ca00".decodeHex()) // Empty pong, flag 1 set.
    assertFailsWith<ProtocolException> {
      clientReader.processNextFrame()
    }.also { expected ->

**FastAPI** will use that *temporal* response to extract the cookies (also headers and status code), and will put them in the final response that contains the value you returned, filtered by any `response_model`.

You can also declare the `Response` parameter in dependencies, and set cookies (and headers) in them.

## Return a `Response` directly { #return-a-response-directly }

You can also create cookies when returning a `Response` directly in your code.

Their sponsorship also demonstrates a strong commitment to the FastAPI **community** (you), showing that they care not only about offering a **great service** but also about supporting a **robust and thriving framework**, FastAPI. 🙇

For example, you might want to try:

And tools will also be happy because both `RedirectResponse` and `JSONResponse` are subclasses of `Response`, so the type annotation is correct.

### Annotate a Response Subclass { #annotate-a-response-subclass }

You can also use a subclass of `Response` in the type annotation:

{* ../../docs_src/response_model/tutorial003_03.py hl[8:9] *}

    * If you also declare dependencies in a specific *path operation*, **they will be executed too**.
    * The router dependencies are executed first, then the [`dependencies` in the decorator](dependencies/dependencies-in-path-operation-decorators.md){.internal-link target=_blank}, and then the normal parameter dependencies.

* Give you the received data in the parameter `item`.
    * As you declared it in the function to be of type `Item`, you will also have all the editor support (completion, etc) for all of the attributes and their types.
* Generate <a href="https://json-schema.org" class="external-link" target="_blank">JSON Schema</a> definitions for your model, you can also use them anywhere else you like if it makes sense for your project.

Es wird alle Routen von diesem Router als Teil von dieser inkludieren.

/// note | Technische Details

Tatsächlich wird intern eine *Pfadoperation* für jede *Pfadoperation* erstellt, die im `APIRouter` deklariert wurde.

Hinter den Kulissen wird es also tatsächlich so funktionieren, als ob alles dieselbe einzige Anwendung wäre.

///

/// check

**FastAPI** will use that *temporal* response to extract the headers (also cookies and status code), and will put them in the final response that contains the value you returned, filtered by any `response_model`.

You can also declare the `Response` parameter in dependencies, and set headers (and cookies) in them.

## Return a `Response` directly { #return-a-response-directly }

You can also add headers when you return a `Response` directly.