////

This means:

* The variable `prices` is a `dict`:
    * The keys of this `dict` are of type `str` (let's say, the name of each item).
    * The values of this `dict` are of type `float` (let's say, the price of each item).

#### Union

You can declare that a variable can be any of **several types**, for example, an `int` or a `str`.

![editor support](https://fastapi.tiangolo.com/img/pycharm-completion.png)

以前は不可能だと考えていたコードでさえ補完されます。例えば、リクエストからのJSONボディ（ネストされている可能性がある）内の `price`キーです。

間違ったキー名を入力したり、ドキュメント間を行き来したり、上下にスクロールして`username`と`user_name`のどちらを使用したか調べたりする必要はもうありません。

### 簡潔

すべてに適切な**デフォルト**があり、オプションの構成ができます。必要なことを実行し、必要なAPIを定義するためにすべてのパラメーターを調整できます。

ただし、デフォルトでもすべて **うまくいきます**。

   */
  public List<Integer> asList() {
    /*
     * Typically we cache this kind of thing, but much repeated use of this view is a performance
     * anti-pattern anyway. If we cache, then everyone pays a price in memory footprint even if
     * they never use this method.
     */
    return new AsList(this);
  }

  static class AsList extends AbstractList<Integer> implements RandomAccess, Serializable {

 *
 * <p>This class should not be assumed to be universally superior to {@code java.util.HashSet}.
 * Generally speaking, this class reduces object allocation and memory consumption at the price of
 * moderately increased constant factors of CPU. Only use this class when there is a specific reason
 * to prioritize memory over CPU.
 *
 * @author Dimitris Andreou
 * @author Jon Noack
 */

   */
  public List<Double> asList() {
    /*
     * Typically we cache this kind of thing, but much repeated use of this view is a performance
     * anti-pattern anyway. If we cache, then everyone pays a price in memory footprint even if
     * they never use this method.
     */
    return new AsList(this);
  }

  static class AsList extends AbstractList<Double> implements RandomAccess, Serializable {

this license or the ordinary General Public License is the better
strategy to use in any particular case, based on the explanations below.

  When we speak of free software, we are referring to freedom of use,
not price.  Our General Public Licenses are designed to make sure that
you have the freedom to distribute copies of free software (and charge
for this service if you wish); that you receive source code or can get

Comme les paramètres sont décrits avec des types TypeScript (similaires aux type hints de Python), la prise en charge
par l'éditeur est assez bonne.

"nici", "nimeni", "nişte", "noastră", "noastre", "noi", "noştri", "nostru", "nu", "ori", "oricând", "oricare", "oricât", "orice", "oricînd", "oricine", "oricît", "oricum", "oriunde", "până", "pe", "pentru", "peste", "pînă", "poate", "pot", "prea", "prima", "primul", "prin", "printr", "sa", "să", "săi", "sale", "sau", "său", "se", "şi", "sînt", "sîntem", "sînteţi", "spre", "sub", "sunt", "suntem", "sunteţi", "ta", "tăi", "tale", "tău", "te", "ţi", "ţie", "tine", "toată", "toate", "tot", "toţi", "totuşi",...

"nici", "nimeni", "nişte", "noastră", "noastre", "noi", "noştri", "nostru", "nu", "ori", "oricând", "oricare", "oricât", "orice", "oricînd", "oricine", "oricît", "oricum", "oriunde", "până", "pe", "pentru", "peste", "pînă", "poate", "pot", "prea", "prima", "primul", "prin", "printr", "sa", "să", "săi", "sale", "sau", "său", "se", "şi", "sînt", "sîntem", "sînteţi", "spre", "sub", "sunt", "suntem", "sunteţi", "ta", "tăi", "tale", "tău", "te", "ţi", "ţie", "tine", "toată", "toate", "tot", "toţi", "totuşi",...

Software Foundation software is covered by the GNU Library General
Public License instead.) You can apply it to your programs, too.

When we speak of free software, we are referring to freedom, not price.
Our General Public Licenses are designed to make sure that you have the
freedom to distribute copies of free software (and charge for this
service if you wish), that you receive source code or can get it if you