Porém se você especificou uma classe de retorno com o valor `None` como media type, o FastAPI utilizará `application/json` para qualquer retorno adicional que possui um modelo associado.

///

## Combinando informações

  /** The request URL built using the request line, headers, and local host name. */
  public val url: HttpUrl,
  /** All headers. */
  public val headers: Headers,
  /** The body of this request, or null if it has none. This may be truncated. */
  public val body: ByteString?,
  /** The total size of the body of this request (before truncation).*/
  public val bodySize: Long,
  /**

   *
   * <p>If the function throws an exception, that exception is used as the result of the derived
   * {@code ClosingFuture}. But if the exception is thrown after the function creates a {@code
   * ClosingFuture}, then none of the closeable objects in that {@code ClosingFuture} will be
   * closed.
   *
   * <p>Usage guidelines for this method:
   *
   * <ul>

  SUBSET_VIEW,
  DESCENDING_VIEW,

  /**
   * For documenting collections that support no optional features, such as {@link
   * java.util.Collections#emptySet}
   */
  NONE;

  private final Set<Feature<? super Collection>> implied;

  CollectionFeature(Feature<? super Collection>... implied) {
    this.implied = copyToSet(implied);
  }

  @Override

     *
     * @param artifact The artifact whose available versions should be determined, must not be {@code null}.
     * @return The available versions of the artifact or an empty list if none, never {@code null}.
     * @since 3.0-alpha-3
     */
    List<String> findVersions(Artifact artifact);

    /**

	public static final field BODY Lokhttp3/logging/HttpLoggingInterceptor$Level;
	public static final field HEADERS Lokhttp3/logging/HttpLoggingInterceptor$Level;
	public static final field NONE Lokhttp3/logging/HttpLoggingInterceptor$Level;
	public static fun getEntries ()Lkotlin/enums/EnumEntries;
	public static fun valueOf (Ljava/lang/String;)Lokhttp3/logging/HttpLoggingInterceptor$Level;

그리고 다음과 같이 호출하면:

```Python
print(user_dict)
```

Python의 `dict`가 다음과 같이 출력됩니다:

```Python
{
    'username': 'john',
    'password': 'secret',
    'email': '******@****.***',
    'full_name': None,
}
```

#### `dict` 언패킹(Unpacking)

`user_dict`와 같은 `dict`를 함수(또는 클래스)에 `**user_dict`로 전달하면, Python은 이를 "언팩(unpack)"합니다. 이 과정에서 `user_dict`의 키와 값을 각각 키-값 인자로 직접 전달합니다.

따라서, 위에서 생성한 `user_dict`를 사용하여 다음과 같이 작성하면:

   * Updates the value currently associated with {@code key} by combining it with {@code x} via the
   * specified accumulator function, returning the new value. The previous value associated with
   * {@code key} (or zero, if there is none) is passed as the first argument to {@code
   * accumulatorFunction}, and {@code x} is passed as the second argument.
   *
   * @since 21.0
   */
  @CanIgnoreReturnValue

              <outputFilename>maven-skinny-bom.xml</outputFilename>
              <reactorDependencies>REACTOR</reactorDependencies>
              <transitiveDependencies>NONE</transitiveDependencies>
              <usePropertiesForVersion>true</usePropertiesForVersion>
              <attach>true</attach>
            </configuration>
          </execution>
          <execution>

///

## Optional File Upload { #optional-file-upload }

You can make a file optional by using standard type annotations and setting a default value of `None`:

{* ../../docs_src/request_files/tutorial001_02_an_py310.py hl[9,17] *}

## `UploadFile` with Additional Metadata { #uploadfile-with-additional-metadata }