* iterator supports it.
   *
   * <p><b>{@code Stream} equivalent:</b> use nested calls to {@link Stream#concat}, or see the
   * advice in {@link #concat(Iterable...)}.
   *
   * @since 20.0
   */
  public static <T extends @Nullable Object> FluentIterable<T> concat(
      Iterable<? extends T> a, Iterable<? extends T> b, Iterable<? extends T> c) {

つまり、Pythonが環境変数から読み取る**あらゆる値**は **`str`型となり**、他の型への変換やバリデーションはコード内で行う必要があります。

環境変数を使用して**アプリケーション設定**を管理する方法については、[高度なユーザーガイド - Settings and Environment Variables](./advanced/settings.md){.internal-link target=_blank}で詳しく学べます。

## `PATH`環境変数

**`PATH`**という**特別な**環境変数があります。この環境変数は、OS（Linux、macOS、Windows）が実行するプログラムを発見するために使用されます。

### Повернення Response напряму

Найпоширенішим випадком буде [повернення Response напряму, як пояснюється пізніше у розширеній документації](../advanced/response-directly.md){.internal-link target=_blank}.

{* ../../docs_src/response_model/tutorial003_02.py hl[8,10:11] *}

### Возвращаем Response

Самый частый сценарий использования - это [возвращать Response напрямую, как описано в расширенной документации](../advanced/response-directly.md){.internal-link target=_blank}.

{* ../../docs_src/response_model/tutorial003_02.py hl[8,10:11] *}

 *
 *  * DER: Distinguished Encoding Rules. This further constrains ASN.1 for deterministic encoding.
 *  * BER: Basic Encoding Rules.
 *
 * This class was implemented according to the [X.690 spec][[x690]], and under the advice of
 * [Lets Encrypt's ASN.1 and DER][asn1_and_der] guide.
 *
 * [x690]: https://www.itu.int/rec/T-REC-X.690
 * [asn1_and_der]: https://letsencrypt.org/docs/a-warm-welcome-to-asn1-and-der/
 */
internal class DerReader(

### Eine Response direkt zurückgeben

Der häufigste Anwendungsfall ist, wenn Sie [eine Response direkt zurückgeben, wie es später im Handbuch für fortgeschrittene Benutzer erläutert wird](../advanced/response-directly.md){.internal-link target=_blank}.

{* ../../docs_src/response_model/tutorial003_02.py hl[8,10:11] *}

<p>
The Go memory model specifies the conditions under which
reads of a variable in one goroutine can be guaranteed to
observe values produced by writes to the same variable in a different goroutine.
</p>


<h3 id="advice">Advice</h3>

<p>
Programs that modify data being simultaneously accessed by multiple goroutines
must serialize such access.
</p>

<p>

        final ExceptionMessageBuilder br = new ExceptionMessageBuilder();
        br.addNotice("Too long boundary size so treats it as 404.");
        br.addItem("Advice");
        br.addElement("Against for CVE-2014-0050 (JVN14876762).");
        br.addElement("Boundary size is limited by Framework.");

This is because FastAPI uses this `root_path` to create the default `server` in OpenAPI with the URL provided by `root_path`.

## Additional servers { #additional-servers }

/// warning

This is a more advanced use case. Feel free to skip it.

///

By default, **FastAPI** will create a `server` in the OpenAPI schema with the URL for the `root_path`.

///

This is a very simple and short tutorial, if you want to learn about databases in general, about SQL, or more advanced features, go to the <a href="https://sqlmodel.tiangolo.com/" class="external-link" target="_blank">SQLModel docs</a>.

## Install `SQLModel` { #install-sqlmodel }