collectValueFromNonCancelledFuture(index, future);
      }
    } finally {
      /*
       * "null" means: There is no need to access `futures` again during
       * `processCompleted` because we're reading each value during a call to
       * handleOneInputDone.
       */
      decrementCountAndMaybeComplete(null);
    }
  }

  /**

"Context Managers" are any of those Python objects that you can use in a `with` statement.

For example, [you can use `with` to read a file](https://docs.python.org/3/tutorial/inputoutput.html#reading-and-writing-files):

```Python
with open("./somefile.txt") as f:
    contents = f.read()
    print(contents)
```

### "컨텍스트 관리자"란 { #what-are-context-managers }

"컨텍스트 관리자"는 Python에서 `with` 문에서 사용할 수 있는 모든 객체를 의미합니다.

예를 들어, [with를 사용해 파일을 읽을 수 있습니다](https://docs.python.org/3/tutorial/inputoutput.html#reading-and-writing-files):

```Python
with open("./somefile.txt") as f:
    contents = f.read()
    print(contents)
```

내부적으로 `open("./somefile.txt")` 는 "컨텍스트 관리자(Context Manager)"라고 불리는 객체를 생성합니다.

	// Object operations.

	// GetObjectNInfo returns a GetObjectReader that satisfies the
	// ReadCloser interface. The Close method runs any cleanup
	// functions, so it must always be called after reading till EOF
	//
	// IMPORTANTLY, when implementations return err != nil, this
	// function MUST NOT return a non-nil ReadCloser.

  }

  /**
   * Read 100 MiB of 'a' chars. This was really slow due to a performance bug in [MultipartReader],
   * and will be really slow if we regress the fix for that.
   */
  @Test
  fun `reading a large part with small byteCount`() {
    val multipartBody =
      MultipartBody
        .Builder("foo")
        .addPart(
          headersOf("header-name", "header-value"),
          object : RequestBody() {

{* ../../docs_src/settings/app02_an_py310/test_main.py hl[9:10,13,21] *}

在相依覆寫中，我們在建立新的 `Settings` 物件時設定 `admin_email` 的新值，然後回傳該新物件。

接著我們就可以測試它是否被使用。

## 讀取 `.env` 檔 { #reading-a-env-file }

如果你有許多設定，而且在不同環境中可能常常變動，將它們放在一個檔案中，然後像讀取環境變數一樣自該檔案讀取，可能會很實用。

這種作法很常見，這些環境變數通常放在 `.env` 檔中，而該檔案被稱為「dotenv」。

/// tip

在類 Unix 系統（如 Linux 與 macOS）中，以點（`.`）開頭的檔案是隱藏檔。

{* ../../docs_src/settings/app02_an_py310/test_main.py hl[9:10,13,21] *}

依存関係オーバーライドでは、新しい `Settings` オブジェクトを作る際に `admin_email` に新しい値を設定し、その新しいオブジェクトを返します。

そして、それが使用されていることをテストできます。

## `.env` ファイルの読み込み { #reading-a-env-file }

変更が多くなりそうな設定が多数ある場合、環境ごとにファイルに入れて、環境変数としてそこから読み込むと便利なことがあります。

このプラクティスは十分に一般的で名前もあり、これらの環境変数は通常 `.env` というファイルに置かれ、そのファイルは「dotenv」と呼ばれます。

/// tip | 豆知識

// of the line. The returned buffer is only valid until the next call to
// ReadLine. ReadLine either returns a non-nil line or it returns an error,
// never both.
//
// The text returned from ReadLine does not include the line end ("\r\n" or "\n").
// No indication or error is given if the input ends without a final line end.
// Calling [Reader.UnreadByte] after ReadLine will always unread the last byte read

Hello again.

////

//// tab | Info

The only hard rule for headings is that the LLM leaves the hash part inside curly brackets unchanged, which ensures that links do not break.

See section `### Headings` in the general prompt in `scripts/translate.py`.

For some language specific instructions, see e.g. section `### Headings` in `docs/de/llm-prompt.md`.

////

        try {
            context.extensions = readCoreExtensionsDescriptor(context);
        } catch (Exception e) {
            context.parsingFailed = true;
            parserRequest.logger().error("Error reading core extensions descriptor", e);
        }

        // CI detection
        context.ciInfo = detectCI(context);

        // only if not failed so far; otherwise we may have no options to validate