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

Internamente, `open("./somefile.txt")` crea un objeto llamado "Context Manager".

Cuando el bloque `with` termina, se asegura de cerrar el archivo, incluso si hubo excepciones.

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

Im Hintergrund erstellt das `open("./somefile.txt")` ein Objekt, das als „Kontextmanager“ bezeichnet wird.

-size:1.75rem!important}.fs-4{font-size:1.5rem!important}}@media print{.d-print-inline{display:inline!important}.d-print-inline-block{display:inline-block!important}.d-print-block{display:block!important}.d-print-grid{display:grid!important}.d-print-inline-grid{display:inline-grid!important}.d-print-table{display:table!important}.d-print-table-row{display:table-row!important}.d-print-table-cell{display:table-cell!important}.d-print-flex{display:flex!important}.d-print-inline-flex{display:inline-...

# protobuf dependencies ourselves. By default this value is false, but some 
# projects enable it, which we don't want here.
# common --define=use_fast_cpp_protos=true

# Make Bazel print out all options from rc files.
common --announce_rc

# TODO(mihaimaruseac): Document this option or remove if no longer needed
common --define=grpc_no_ares=true

////

## Pythonで環境変数を読み取る

環境変数をPythonの**外側**、ターミナル（や他の方法）で作成し、**Python内で読み取る**こともできます。

例えば、以下のような`main.py`ファイルを用意します:

```Python hl_lines="3"
import os

name = os.getenv("MY_NAME", "World")
print(f"Hello {name} from Python")
```

/// tip

<a href="https://docs.python.org/3.8/library/os.html#os.getenv" class="external-link" target="_blank">`os.getenv()`</a> の第2引数は、デフォルトで返される値を指定します。

### Synchronous Get ([.kt][SynchronousGetKotlin], [.java][SynchronousGetJava])

Download a file, print its headers, and print its response body as a string.

////

### 在 Python 中读取环境变量

您还可以在 Python 之外的地方（例如终端中或使用任何其他方法）创建环境变量，然后在 Python 中读取它们。

例如，您可以有一个名为 `main.py` 的文件，其中包含以下内容：

```Python hl_lines="3"
import os

name = os.getenv("MY_NAME", "World")
print(f"Hello {name} from Python")
```

/// tip

<a href="https://docs.python.org/3.8/library/os.html#os.getenv" class="external-link" target="_blank">`os.getenv()`</a> 的第二个参数是要返回的默认值。

}

var bmbuf []byte

func valName(x int) string {
	if s := x >> 20; s<<20 == x {
		return fmt.Sprintf("%dM", s)
	}
	if s := x >> 10; s<<10 == x {
		return fmt.Sprintf("%dK", s)
	}
	return fmt.Sprint(x)
}

func benchBytes(b *testing.B, sizes []int, f func(b *testing.B, n int)) {
	for _, n := range sizes {
		if isRaceBuilder && n > 4<<10 {
			continue
		}
		b.Run(valName(n), func(b *testing.B) {

- kubectl: `--use-openapi-print-columns` has been deprecated in favor of `--server-print`, and will be removed in a future version. ([#65601](https://github.com/kubernetes/kubernetes/pull/65601), [@liggitt](https://github.com/liggitt))

		a.setInt(i)
		return nil
	}

	if f, ok := a.bytesToFloat(); ok {
		a.setFloat(f)
		return nil
	}
	var s string
	if v, ok := a.value.([]byte); ok {
		s = string(v)
	} else {
		s = fmt.Sprint(a.value)
	}
	err := fmt.Errorf("Could not convert %q to a number", s)
	return errInvalidDataType(err)
}

// All the bytesTo* functions defined below assume the value is a byte-slice.