Isso ocorre porque o **OAuth2** usa "dados de um formulário" para mandar o **username** e **senha**.

Execute esse exemplo com:

<div class="termy">

```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)
```

</div>

## Verifique-o

   * ("constant lists"). Example:
   *
   * <pre>{@code
   * public static final ImmutableList<Color> GOOGLE_COLORS
   *     = new ImmutableList.Builder<Color>()
   *         .addAll(WEBSAFE_COLORS)
   *         .add(new Color(0, 191, 255))
   *         .build();
   * }</pre>
   *
   * <p>Elements appear in the resulting list in the same order they were added to the builder.

    local-prefixes: istio.io/
  misspell:
    # Correct spellings using locale preferences for US or UK.
    # Default is to use a neutral variety of English.
    # Setting locale to US will correct the British spelling of 'colour' to 'color'.
    locale: US
    ignore-words:
      - cancelled
  lll:
    # max line length, lines longer will be reported. Default is 120.

package cmd

import (
	"context"
	"encoding/json"
	"errors"
	"fmt"
	"io/fs"
	"os"
	"sync"

	"github.com/dustin/go-humanize"
	"github.com/minio/minio/internal/color"
	"github.com/minio/minio/internal/config"
	"github.com/minio/minio/internal/config/storageclass"
	xioutil "github.com/minio/minio/internal/ioutil"
	"github.com/minio/minio/internal/logger"

</a>
<a href="https://pypi.org/project/fastapi" target="_blank">
    <img src="https://img.shields.io/pypi/v/fastapi?color=%2334D058&label=pypi%20package" alt="Package version">
</a>
<a href="https://pypi.org/project/fastapi" target="_blank">
    <img src="https://img.shields.io/pypi/pyversions/fastapi.svg?color=%2334D058" alt="Supported Python versions">
</a>
</p>

---

{* ../../docs_src/sql_databases/tutorial001_an_py310.py ln[66:73] hl[71] *}

### Run the App

You can run the app:

<div class="termy">

```console
$ fastapi dev main.py

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

</div>

pkg image/color, type Gray16 struct
pkg image/color, type Gray16 struct, Y uint16
pkg image/color, type Model interface { Convert }
pkg image/color, type Model interface, Convert(Color) Color
pkg image/color, type NRGBA struct
pkg image/color, type NRGBA struct, A uint8
pkg image/color, type NRGBA struct, B uint8
pkg image/color, type NRGBA struct, G uint8
pkg image/color, type NRGBA struct, R uint8

                                                    <td>
                                                        <em class="fa fa-folder-open" style="color:#F7C502;">
                                                            ${f:h(data.name)}
                                                    </td>
                                                    <td></td>

Das, weil **OAuth2** „Formulardaten“ zum Senden von `username` und `password` verwendet.

///

Führen Sie das Beispiel aus mit:

<div class="termy">

```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)
```

</div>

## Überprüfen

安装命令： `pip install python-multipart`。

这是因为 **OAuth2** 使用**表单数据**发送 `username` 与 `password`。

///

用下面的命令运行该示例：

<div class="termy">

```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)
```

</div>

## 查看文档