Por ejemplo, podrías tener un archivo `main.py` con:

```Python hl_lines="3"
import os

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

/// tip | Consejo

El segundo argumento de <a href="https://docs.python.org/3.8/library/os.html#os.getenv" class="external-link" target="_blank">`os.getenv()`</a> es el valor por defecto a retornar.

    object : ThreadFactory {
      private var nextId = 1

      override fun newThread(runnable: Runnable): Thread = Thread(runnable, "$name-${nextId++}")
    }
}

fun getEnv(name: String) = System.getenv(name)

val SYSTEM_FILE_SYSTEM = FileSystem.SYSTEM

            if (connected) {
                return;
            }
            final String endpoint = System.getenv().get("S3_ENDPOINT");
            final String accessKey = System.getenv().get("S3_ACCESS_KEY");
            final String secretKey = System.getenv().get("S3_SECRET_KEY");
            final String region = System.getenv().getOrDefault("S3_REGION", "us-east-1");

            // Validate endpoint before attempting connection

include(":samples:tlssurvey")
include(":samples:unixdomainsockets")
include(":container-tests")
include(":module-tests")

project(":okhttp-logging-interceptor").name = "logging-interceptor"

val androidHome = System.getenv("ANDROID_HOME")
val localProperties = Properties().apply {
  val file = rootProject.projectDir.resolve("local.properties")
  if (file.exists()) {
    load(file.inputStream())
  }
}

                return;
            }
            final String endpoint = System.getenv().get("STORAGE_ENDPOINT");
            final String accessKey = System.getenv().get("STORAGE_ACCESS_KEY");
            final String secretKey = System.getenv().get("STORAGE_SECRET_KEY");
            final String region = System.getenv().get("STORAGE_REGION");

            // Validate endpoint before attempting connection

 * limitations under the License.
 */
package okhttp3

import okio.Buffer
import okio.Path
import okio.Path.Companion.toPath

val okHttpRoot: Path
  get() = getEnv("OKHTTP_ROOT")!!.toPath()

fun String(vararg codePoints: Int): String {
  val buffer = Buffer()
  for (codePoint in codePoints) {
    buffer.writeUtf8CodePoint(codePoint)
  }
  return buffer.readUtf8()

    importlib.reload(tutorial001_py39)

    client = TestClient(tutorial001_py39.app)
    return client


def test_disable_openapi(monkeypatch):
    monkeypatch.setenv("OPENAPI_URL", "")
    # Load the client after setting the env var
    client = get_client()
    response = client.get("/openapi.json")
    assert response.status_code == 404, response.text
    response = client.get("/docs")

Например, у вас есть файл `main.py`:

```Python hl_lines="3"
import os

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

/// tip | Совет

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.

    public static final String NAME = "TeamCity";

    private static final String TEAMCITY_VERSION = "TEAMCITY_VERSION";

    @Override
    public Optional<CIInfo> detectCI() {
        String ciEnv = System.getenv(TEAMCITY_VERSION);
        if (ciEnv != null && !ciEnv.trim().isEmpty()) {
            return Optional.of(new CIInfo() {
                @Override
                public String name() {
                    return NAME;

import os
from typing import Any

from pdm.backend.hooks import Context

TIANGOLO_BUILD_PACKAGE = os.getenv("TIANGOLO_BUILD_PACKAGE", "fastapi")


def pdm_build_initialize(context: Context) -> None:
    metadata = context.config.metadata
    # Get custom config for the current package, from the env var
    config: dict[str, Any] = context.config.data["tool"]["tiangolo"][
        "_internal-slim-build"
    ]["packages"].get(TIANGOLO_BUILD_PACKAGE)