"content": {
                                "application/json": {
                                    "schema": {
                                        "$ref": "#/components/schemas/HTTPValidationError"
                                    }
                                }
                            },
                        },
                    },

                            "content": {
                                "application/json": {
                                    "schema": {
                                        "$ref": "#/components/schemas/HTTPValidationError"
                                    }
                                }
                            },
                        },
                    },

 * complete}. If the computation has already completed when the listener is added, the listener will
 * execute immediately.
 *
 * <p>See the Guava User Guide article on <a
 * href="https://github.com/google/guava/wiki/ListenableFutureExplained">{@code
 * ListenableFuture}</a>.
 *
 * <p>This class is GWT-compatible.
 *
 * <h3>Purpose</h3>
 *

## 尝试一下

如果您的文件名为 `main.py`，请使用以下命令运行应用程序：

```console
$ uvicorn main:app --reload

<span style="color: green;">INFO</span>:     Uvicorn running on http://127.0.0.1:8000 (Press CTRL+C to quit)
```

在浏览器中打开 <a href="http://127.0.0.1:8000" class="external-link" target="_blank">http://127.0.0.1:8000</a>。

您将看到一个简单的页面，如下所示：

<img src="/img/tutorial/websockets/image01.png">

您可以在输入框中输入消息并发送：

                    "requestBody": {
                        "content": {
                            "application/json": {
                                "schema": {"$ref": "#/components/schemas/Subscription"}
                            }
                        },
                        "required": True,
                    },
                    "responses": {

///

## Overriding the defaults

Using the information above, you can use the same utility function to generate the OpenAPI schema and override each part that you need.

For example, let's add <a href="https://github.com/Rebilly/ReDoc/blob/master/docs/redoc-vendor-extensions.md#x-logo" class="external-link" target="_blank">ReDoc's OpenAPI extension to include a custom logo</a>.

### Normal **FastAPI**

# Form Data

When you need to receive form fields instead of JSON, you can use `Form`.

/// info

To use forms, first install <a href="https://github.com/Kludex/python-multipart" class="external-link" target="_blank">`python-multipart`</a>.

Make sure you create a [virtual environment](../virtual-environments.md){.internal-link target=_blank}, activate it, and then install it, for example:

```console
$ pip install python-multipart
```

///

            if (v.full_name === 'fastapi/fastapi') {
                return
            }
            const li = document.createElement('li')
            li.innerHTML = `<a href="${v.html_url}" target="_blank">★ ${v.stargazers_count} - ${v.full_name}</a> by <a href="${v.owner.html_url}" target="_blank">@${v.owner.login}</a>`
            ul.append(li)
        })
    }

    setupTermynal();

                            "content": {
                                "image/png": {},
                                "application/json": {
                                    "schema": {"$ref": "#/components/schemas/Item"}
                                },
                            },
                        },
                        "422": {
                            "description": "Validation Error",

Starlette (und **FastAPI**) basiert auf <a href="https://anyio.readthedocs.io/en/stable/" class="external-link" target="_blank">AnyIO</a>, was bedeutet, es ist sowohl kompatibel mit der Python-Standardbibliothek <a href="https://docs.python.org/3/library/asyncio-task.html" class="external-link" target="_blank">asyncio</a>, als auch mit <a href="https://trio.readthedocs.io/en/stable/" class="external-link" target="_blank">Trio</a>.