* values are even integers; this method returns the one that is a multiple of a greater power of
   * two.)
   *
   * @throws ArithmeticException if {@code mode} is {@link RoundingMode#UNNECESSARY} and {@code x}
   *     is not precisely representable as a {@code double}
   * @since 30.0
   */
  public static double roundToDouble(BigDecimal x, RoundingMode mode) {

```Python hl_lines="7"
{!../../docs_src/request_forms/tutorial001.py!}
```

Por exemplo, em uma das maneiras que a especificação OAuth2 pode ser usada (chamada "fluxo de senha"), é necessário enviar um `username` e uma `password` como campos do formulário.

    runs-on: ubuntu-latest
    strategy:
      matrix:
        python-version: [python3.9, python3.10, python3.11, python3.12]
    steps:
      - name: Delete unnecessary tools folder
        run: rm -rf /opt/hostedtoolcache
      -
        name: Checkout
        uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
      -
        name: Set up Docker Buildx

Ce chapitre n'est qu'un **tutoriel rapide / rappel** sur les annotations de type Python.
Seulement le minimum nécessaire pour les utiliser avec **FastAPI** sera couvert... ce qui est en réalité très peu.

**FastAPI** est totalement basé sur ces annotations de type, qui lui donnent de nombreux avantages.

   * leaking resources callers must [close the response body][ResponseBody] or the response.
   *
   * Note that transport-layer success (receiving a HTTP response code, headers and body) does not
   * necessarily indicate application-layer success: `response` may still indicate an unhappy HTTP
   * response code like 404 or 500.
   *
   * @throws IOException if the request could not be executed due to cancellation, a connectivity

# Extendendo o OpenAPI

Existem alguns casos em que pode ser necessário modificar o esquema OpenAPI gerado.

Nesta seção, você verá como fazer isso.

## O processo normal

O processo normal (padrão) é o seguinte:

Uma aplicação (instância) do `FastAPI` possui um método `.openapi()` que deve retornar o esquema OpenAPI.

      return this;
    }

    @Override
    public HashCode hash() {
      return hashBytes(stream.byteArray(), 0, stream.length());
    }
  }

  // Just to access the byte[] without introducing an unnecessary copy
  private static final class ExposedByteArrayOutputStream extends ByteArrayOutputStream {
    ExposedByteArrayOutputStream(int expectedInputSize) {
      super(expectedInputSize);
    }

    strategy:
      matrix:
        python-version: [python3.9, python3.10, python3.11, python3.12]
    permissions:
      contents: read
      pull-requests: write
    steps:
      - name: Delete unnecessary tools folder
        run: |
          df -h
          rm -rf /opt/hostedtoolcache
          df -h
      -
        name: Checkout
        uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2

  /** Returns true if this adapter can read [header] in a choice. */
  fun matches(header: DerHeader): Boolean

  /**
   * Returns a value from this adapter.
   *
   * This must always return a value, though it doesn't necessarily need to consume data from
   * [reader]. For example, if the reader's peeked tag isn't readable by this adapter, it may return
   * a default value.
   *

       */
      return;
    }

    /*
     * Only under Windows (or hypothetically when running with some other non-POSIX, ACL-based
     * filesystem) does our prod code look up the username. Thus, this test doesn't necessarily test
     * anything interesting under most environments. Still, we can run it (except for Android, at
     * least old versions), so we mostly do. This is useful because we don't actually run our CI on