use, offer to sell, sell, import, and otherwise transfer the Work,
      where such license applies only to those patent claims licensable
      by such Contributor that are necessarily infringed by their
      Contribution(s) alone or by combination of their Contribution(s)
      with the Work to which such Contribution(s) was submitted. If You
      institute patent litigation against any entity (including a

      use, offer to sell, sell, import, and otherwise transfer the Work,
      where such license applies only to those patent claims licensable
      by such Contributor that are necessarily infringed by their
      Contribution(s) alone or by combination of their Contribution(s)
      with the Work to which such Contribution(s) was submitted. If You
      institute patent litigation against any entity (including a

      use, offer to sell, sell, import, and otherwise transfer the Work,
      where such license applies only to those patent claims licensable
      by such Contributor that are necessarily infringed by their
      Contribution(s) alone or by combination of their Contribution(s)
      with the Work to which such Contribution(s) was submitted. If You
      institute patent litigation against any entity (including a

        }
        list.add(text);
    }

    /**
     * Gets the default field keywords from the field log.
     * @return List of keywords for the default field, or empty list if none.
     */
    public List<String> getDefaultKeyword() {
        if (fieldLogMap != null) {
            return fieldLogMap.getOrDefault(Constants.DEFAULT_FIELD, Collections.emptyList());
        }

But if you have specified a custom response class with `None` as its media type, FastAPI will use `application/json` for any additional response that has an associated model.

///

## Combining information { #combining-information }

c,d,e,f=[],g=0,h=a.length;h>g;g++)d=a[g],d.style&&(f[g]=L.get(d,"olddisplay"),c=d.style.display,b?(f[g]||"none"!==c||(d.style.display=""),""===d.style.display&&S(d)&&(f[g]=L.access(d,"olddisplay",tb(d.nodeName)))):(e=S(d),"none"===c&&e||L.set(d,"olddisplay",e?c:n.css(d,"display"))));for(g=0;h>g;g++)d=a[g],d.style&&(b&&"none"!==d.style.display&&""!==d.style.display||(d.style.display=b?f[g]||"":"none"));return a}n.extend({cssHooks:{opacity:{get:function(a,b){if(b){var c=xb(a,"opacity");return""===c?"1...

    * この`dict`の値は`float`型です。（つまり、各項目の価格）

#### `Optional`

また、`Optional`を使用して、変数が`str`のような型を持つことを宣言することもできますが、それは「オプション」であり、`None`にすることもできます。

```Python hl_lines="1 4"
{!../../docs_src/python_types/tutorial009.py!}
```

ただの`str`の代わりに`Optional[str]`を使用することで、エディタは値が常に`str`であると仮定している場合に実際には`None`である可能性があるエラーを検出するのに役立ちます。

#### ジェネリック型

以下のように角括弧で型パラメータを取る型を:

* `List`
* `Tuple`
* `Set`
* `Dict`

        DirectoryCacheEntry entry = directoryCache.get(directoryPath);
        if (entry == null)
            return;

        // Handle lease break by updating cache behavior
        // Only process if newState is not NONE (0) - a valid lease state
        if (newState != 0) {
            if ((newState & Smb2LeaseState.SMB2_LEASE_READ_CACHING) == 0) {
                // Lost read cache - invalidate directory cache

///

## Subida de Archivos Opcional

Puedes hacer un archivo opcional utilizando anotaciones de tipos estándar y estableciendo un valor por defecto de `None`:

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

## `UploadFile` con Metadatos Adicionales

También puedes usar `File()` con `UploadFile`, por ejemplo, para establecer metadatos adicionales:

Второй аргумент <a href=«https://docs.python.org/3.8/library/os.html#os.getenv» class=«external-link» target=«_blank»>`os.getenv()`</a> - это возвращаемое по умолчанию значение.

Если значение не указано, то по умолчанию оно равно `None`. В данном случае мы указываем `«World»` в качестве значения по умолчанию.
///

Затем можно запустить эту программу на Python:

//// tab | Linux, macOS, Windows Bash

<div class="termy">

```console