then apps are responsible for calling `OkHttp.initialize(applicationContext)` in `Application.onCreate`.

OkHttp depends on [Okio][okio] for high-performance I/O and the [Kotlin standard library][kotlin]. Both are small libraries with strong backward-compatibility.

We highly recommend you keep OkHttp up-to-date. As with auto-updating web browsers, staying current

### Die automatischen Dokumentationen deaktivieren { #disable-the-automatic-docs }

Der erste Schritt besteht darin, die automatischen Dokumentationen zu deaktivieren, da diese standardmäßig das Standard-CDN verwenden.

Um diese zu deaktivieren, setzen Sie deren URLs beim Erstellen Ihrer `FastAPI`-App auf `None`:

{* ../../docs_src/custom_docs_ui/tutorial001_py39.py hl[8] *}

{* ../../docs_src/body/tutorial001_py310.py hl[2] *}

## Ihr Datenmodell erstellen { #create-your-data-model }

Dann deklarieren Sie Ihr Datenmodell als eine Klasse, die von `BaseModel` erbt.

Verwenden Sie Standard-Python-Typen für alle Attribute:

{* ../../docs_src/body/tutorial001_py310.py hl[5:9] *}

Das ist keine Limitation von **FastAPI**, sondern Teil des HTTP-Protokolls.

///

## Optionaler Datei-Upload { #optional-file-upload }

Sie können eine Datei optional machen, indem Sie Standard-Typannotationen verwenden und den Defaultwert auf `None` setzen:

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

## `UploadFile` mit zusätzlichen Metadaten { #uploadfile-with-additional-metadata }

 * implement subtleties of the API improperly.
 *
 * <p><b>Custom implementation</b>: Avoid implementing {@code ListenableFuture} from scratch. If you
 * can't get by with the standard implementations, prefer to derive a new {@code Future} instance
 * with the methods in {@link Futures} or, if necessary, to extend {@link AbstractFuture}.
 *

 * implement subtleties of the API improperly.
 *
 * <p><b>Custom implementation</b>: Avoid implementing {@code ListenableFuture} from scratch. If you
 * can't get by with the standard implementations, prefer to derive a new {@code Future} instance
 * with the methods in {@link Futures} or, if necessary, to extend {@link AbstractFuture}.
 *

# FastAPI CLI

**FastAPI CLI**는 FastAPI 애플리케이션을 실행하고, 프로젝트를 관리하는 등 다양한 작업을 수행할 수 있는 커맨드 라인 프로그램입니다.

FastAPI를 설치할 때 (예: `pip install "fastapi[standard]"` 명령어를 사용할 경우), `fastapi-cli`라는 패키지가 포함됩니다. 이 패키지는 터미널에서 사용할 수 있는 `fastapi` 명령어를 제공합니다.

개발용으로 FastAPI 애플리케이션을 실행하려면 다음과 같이 `fastapi dev` 명령어를 사용할 수 있습니다:

<div class="termy">

```console
$ <font color="#4E9A06">fastapi</font> dev <u style="text-decoration-style:single">main.py</u>

   * </ul>
   *
   * <p>This escaper is suitable for escaping parameter names and values even when <a
   * href="https://www.w3.org/TR/html401/appendix/notes.html#h-B.2.2">using the non-standard
   * semicolon</a>, rather than the ampersand, as a parameter delimiter. Nevertheless, we recommend
   * using the ampersand unless you must interoperate with systems that require semicolons.
   *

/// info

The <a href="https://github.com/Kludex/python-multipart" class="external-link" target="_blank">`python-multipart`</a> package is automatically installed with **FastAPI** when you run the `pip install "fastapi[standard]"` command.

However, if you use the `pip install fastapi` command, the `python-multipart` package is not included by default.

          <description>
            Type of toolchain:&lt;ul>
            &lt;li>{@code jdk} for &lt;a
            href="https://maven.apache.org/plugins/maven-toolchains-plugin/toolchains/jdk.html">JDK Standard Toolchain&lt;/a>,&lt;/li>
            &lt;li>other value for &lt;a
            href="https://maven.apache.org/plugins/maven-toolchains-plugin/toolchains/custom.html">Custom Toolchain&lt;/a>&lt;/li>
            &lt;/ul>