Las variables de entorno pueden ser útiles para manejar **configuraciones** de aplicaciones, como parte de la **instalación** de Python, etc.

## Crear y Usar Variables de Entorno { #create-and-use-env-vars }

Puedes **crear** y usar variables de entorno en la **shell (terminal)**, sin necesidad de Python:

//// tab | Linux, macOS, Windows Bash

<div class="termy">

```console

    CharBuffer empty = CharBuffer.wrap("");
    assertEquals(0, CharStreams.exhaust(empty));
    assertEquals(0, empty.remaining());
  }

  public void testNullWriter() throws Exception {
    // create a null writer
    Writer nullWriter = CharStreams.nullWriter();
    // write to the writer
    nullWriter.write('n');
    String test = "Test string for NullWriter";
    nullWriter.write(test);

    input.addListener(output, rejectionPropagatingExecutor(executor, output));
    return output;
  }

  static <I extends @Nullable Object, O extends @Nullable Object> ListenableFuture<O> create(
      ListenableFuture<I> input, Function<? super I, ? extends O> function, Executor executor) {
    TransformFuture<I, O> output = new TransformFuture<>(input, function);

    CharBuffer empty = CharBuffer.wrap("");
    assertEquals(0, CharStreams.exhaust(empty));
    assertEquals(0, empty.remaining());
  }

  public void testNullWriter() throws Exception {
    // create a null writer
    Writer nullWriter = CharStreams.nullWriter();
    // write to the writer
    nullWriter.write('n');
    String test = "Test string for NullWriter";
    nullWriter.write(test);

///

### Das `Settings`-Objekt erstellen { #create-the-settings-object }

Importieren Sie `BaseSettings` aus Pydantic und erstellen Sie eine Unterklasse, ganz ähnlich wie bei einem Pydantic-Modell.

	// If false only main directory will be scanned.
	// Should always be true if Separator is n SlashSeparator.
	Recursive bool

	// Separator to use.
	Separator string

	// Create indicates that the lister should not attempt to load an existing cache.
	Create bool

	// Include pure directories.
	IncludeDirectories bool

	// Transient is set if the cache is transient due to an error or being a reserved bucket.

        if (domain == null) {
            domain = Type3Message.getDefaultDomain();
        }
        DEFAULT_DOMAIN = domain;
    }

    /**
     * Creates a new NTLM HTTP URL connection that wraps an existing HTTP connection.
     *
     * @param connection the HTTP connection to wrap for NTLM authentication
     */

    /** List of sitemap URLs found in the robots.txt file. */
    private final List<String> sitemapList = new ArrayList<>();

    /**
     * Creates a new RobotsTxt instance.
     */
    public RobotsTxt() {
        // Default constructor
    }

    /**
     * Checks if access to a given path is allowed for a specific user agent according to robots.txt rules.

        if (!model.getMixins().isEmpty() && !flattenEnabled && !model.isPreserveModelVersion()) {
            throw new MavenException("The consumer POM for "
                    + project.getId()
                    + " cannot be created because the POM contains mixins. "
                    + "Mixins are not supported in the default consumer POM format. "
                    + "You have the following options to resolve this:" + System.lineSeparator()

	"github.com/minio/pkg/v3/console"
	"github.com/minio/pkg/v3/wildcard"
	"github.com/minio/pkg/v3/workers"
)

const (
	bgHealingUUID = "0000-0000-0000-0000"
)

// NewBgHealSequence creates a background healing sequence
// operation which scans all objects and heal them.
func newBgHealSequence() *healSequence {
	reqInfo := &logger.ReqInfo{API: "BackgroundHeal"}