absl::Span<const AbstractTensorHandle* const> tensors) const;
  // Unwatches this tensor on the tape. Mainly used for cleanup when deleting
  // eager tensors.
  void DeleteTrace(const AbstractTensorHandle*);

  // Consumes the internal state of the tape (so cannot be called more than
  // once unless the tape is persistent) and produces the gradient of the target
  // tensors with respect to the source tensors. The output gradients are used

# 表单数据 { #form-data }

当你需要接收表单字段而不是 JSON 时，可以使用 `Form`。

/// info

要使用表单，首先安装 [`python-multipart`](https://github.com/Kludex/python-multipart)。

请先创建并激活一个[虚拟环境](../virtual-environments.md)，然后再进行安装，例如：

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

///

## 导入 `Form` { #import-form }

从 `fastapi` 导入 `Form`：

{* ../../docs_src/request_forms/tutorial001_an_py310.py hl[3] *}

	Progress rebalPoolProgress `json:"progress"` // is empty when rebalance is not running
}

// rebalanceAdminStatus holds rebalance status related information exported to mc, console, etc.
type rebalanceAdminStatus struct {
	ID        string                // identifies the ongoing rebalance operation by a uuid
	Pools     []rebalancePoolStatus `json:"pools"` // contains all pools, including inactive

### Die automatische API-Dokumentation testen { #check-the-automatic-api-docs }

Führen Sie nun den Befehl `fastapi` aus:

<div class="termy">

```console
$ fastapi dev

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

</div>

Para usar formularios, primero instala [`python-multipart`](https://github.com/Kludex/python-multipart).

Asegúrate de crear un [entorno virtual](../virtual-environments.md), activarlo, y luego instalarlo, por ejemplo:

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

///

## Importar `Form` { #import-form }

Importar `Form` desde `fastapi`:

{* ../../docs_src/request_forms/tutorial001_an_py310.py hl[3] *}

### Revisa la documentación automática de la API { #check-the-automatic-api-docs }

Ahora, ejecuta el comando `fastapi`:

<div class="termy">

```console
$ fastapi dev

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

</div>

{* ../../docs_src/sub_applications/tutorial001_py310.py hl[11, 19] *}

### Verifique a documentação automática da API { #check-the-automatic-api-docs }

Agora, execute o comando `fastapi`:

<div class="termy">

```console
$ fastapi dev

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

</div>

這裡我們宣告 `openapi_url` 設定，預設值同樣是 `"/openapi.json"`。

接著在建立 `FastAPI` 應用時使用它。

然後你可以將環境變數 `OPENAPI_URL` 設為空字串，以停用 OpenAPI（包含文件 UI），如下：

<div class="termy">

```console
$ OPENAPI_URL= uvicorn main:app

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

</div>

## Встановіть залежності { #install-dependencies }

Переконайтеся, що ви створили [віртуальне оточення](../virtual-environments.md), активували його та встановили `jinja2`:

<div class="termy">

```console
$ pip install jinja2

---> 100%
```

</div>

## Використання `Jinja2Templates` { #using-jinja2templates }

- Імпортуйте `Jinja2Templates`.

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

installieren.

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

///

Führen Sie das Beispiel aus mit:

<div class="termy">

```console
$ fastapi dev