```Python
contents = await myfile.read()
```

在普通 `def` *路径操作函数*  内，则可以直接访问 `UploadFile.file`，例如：

```Python
contents = myfile.file.read()
```

/// note | `async` 技术细节

使用 `async` 方法时，**FastAPI** 在线程池中执行文件方法，并 `await` 操作完成。

///

/// note | Starlette 技术细节

**FastAPI** 的 `UploadFile` 直接继承自 **Starlette** 的 `UploadFile`，但添加了一些必要功能，使之与 **Pydantic** 及 FastAPI 的其它部件兼容。

///

## 什么是 「表单数据」

    <offline>true</offline>
    ]]></configuration>
      <description>
        <![CDATA[
      Flags the system as offline, to prevent accessing the network to resolve artifacts or execute plugins.

      NOTE: It's also possible to switch to offline mode on a per-build basis, using the '-o' command-line option.
    ]]></description>
    </expression>
    <expression>
      <syntax>settings.interactiveMode</syntax>

<dependencies>
  ...
</dependencies>
    ]]></configuration>
    <description>
      <![CDATA[
      This is a set of Artifact instances resolved from the set of dependencies for
      the current project.

      NOTE: This will likely contain much more than the direct dependencies of the
      current POM, since Maven uses transitive, or chained, dependency resolution.
    ]]></description>
  </expression>
  <expression>

<img src="/img/tutorial/response-status-code/image01.png">

/// note

Some response codes (see the next section) indicate that the response does not have a body.

FastAPI knows this, and will produce OpenAPI docs that state there is no response body.

///

## About HTTP status codes { #about-http-status-codes }

/// note

If you already know what HTTP status codes are, skip to the next section.

///

L'opération d'écriture n'utilisant ni `async` ni `await`, on définit la fonction avec un `def` normal.

{* ../../docs_src/background_tasks/tutorial001.py hl[6:9] *}

## Ajouter une tâche d'arrière-plan

Dans votre *fonction de chemin*, passez votre fonction de tâche à l'objet de type `BackgroundTasks` (`background_tasks` ici) grâce à la méthode `.add_task()` :


{* ../../docs_src/background_tasks/tutorial001.py hl[14] *}

@GwtCompatible
public final class Lists {
  private Lists() {}

  // ArrayList

  /**
   * Creates a <i>mutable</i>, empty {@code ArrayList} instance.
   *
   * <p><b>Note:</b> if mutability is not required, use {@link ImmutableList#of()} instead.
   *
   * <p><b>Note:</b> this method is now unnecessary and should be treated as deprecated. Instead,
   * use the {@code ArrayList} {@linkplain ArrayList#ArrayList() constructor} directly, taking

## Importe `Field` { #import-field }

Primeiro, você tem que importá-lo:

{* ../../docs_src/body_fields/tutorial001_an_py310.py hl[4] *}

/// warning | Atenção

Note que `Field` é importado diretamente do `pydantic`, não do `fastapi` como todo o resto (`Query`, `Path`, `Body`, etc).

///

## Declare atributos do modelo { #declare-model-attributes }

Note that due to this extension behavior, AWS SDK's may not support the extension functionality pertaining to replicating versioned deletes.

   * {@code SerializableTester} calls with other, GWT-compatible tests.
   *
   * <p>Note that the specified object may not be known by the compiler to be a {@link
   * java.io.Serializable} instance, and is thus declared an {@code Object}. For example, it might
   * be declared as a {@code List}.
   *
   * <p>Note also that serialization is not in general required to return an object that is

   * the first is returned.
   *
   * <p><b>Implementation note:</b> this method is invoked by the default implementations of the
   * other {@code min} overloads, so overriding it will affect their behavior.
   *
   * <p><b>Note:</b> Consider using {@code Comparators.min(a, b, thisComparator)} instead. If {@code