return () ->
        new Iterator<T>() {
          private final ListIterator<T> listIter = list.listIterator(list.size());

          @Override
          public boolean hasNext() {
            return listIter.hasPrevious();
          }

          @Override
          public T next() {
            return listIter.previous();
          }

          @Override
          public void remove() {

            [Guava's philosophy](https://github.com/google/guava/wiki/PhilosophyExplained), and
            I strongly believe that this proposal aligns with it.
          required: true
        - label: >
            I have visited the [idea graveyard](https://github.com/google/guava/wiki/IdeaGraveyard),
            and did not see anything similar to this idea.

You can define the default value as well as all the extra validation or annotation parameters:

{* ../../docs_src/cookie_params/tutorial001_an_py310.py hl[9] *}

/// note | Technical Details

`Cookie` is a "sister" class of `Path` and `Query`. It also inherits from the same common `Param` class.

But remember that when you import `Query`, `Path`, `Cookie` and others from `fastapi`, those are actually functions that return special classes.

You can define the default value as well as all the extra validation or annotation parameters:

{* ../../docs_src/header_params/tutorial001_an_py310.py hl[9] *}

/// note | Technical Details

`Header` is a "sister" class of `Path`, `Query` and `Cookie`. It also inherits from the same common `Param` class.

import org.eclipse.aether.resolution.DependencyRequest;
import org.eclipse.aether.util.artifact.ArtifactIdUtils;
import org.eclipse.aether.util.graph.manager.DependencyManagerUtils;
import org.eclipse.aether.util.graph.visitor.DependencyGraphDumper;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * @deprecated use {@code org.apache.maven.api.services.ProjectBuilder} instead
 */
@Deprecated(since = "4.0.0")
@Named

 * class CrawlingService extends AbstractScheduledService {
 *   private Set<Uri> visited;
 *   private Queue<Uri> toCrawl;
 *   protected void startUp() throws Exception {
 *     toCrawl = readStartingUris();
 *   }
 *
 *   protected void runOneIteration() throws Exception {
 *     Uri uri = toCrawl.remove();
 *     Collection<Uri> newUris = crawl(uri);
 *     visited.add(uri);
 *     for (Uri newUri : newUris) {

# Incluyendo WSGI - Flask, Django, otros { #including-wsgi-flask-django-others }

Puedes montar aplicaciones WSGI como viste con [Sub Aplicaciones - Mounts](sub-applications.md){.internal-link target=_blank}, [Detrás de un Proxy](behind-a-proxy.md){.internal-link target=_blank}.

Para eso, puedes usar `WSGIMiddleware` y usarlo para envolver tu aplicación WSGI, por ejemplo, Flask, Django, etc.

## Usando `WSGIMiddleware` { #using-wsgimiddleware }

Al desplegar aplicaciones probablemente querrás tener algo de **replicación de procesos** para aprovechar **múltiples núcleos** y poder manejar más requests.

Como viste en el capítulo anterior sobre [Conceptos de Despliegue](concepts.md){.internal-link target=_blank}, hay múltiples estrategias que puedes usar.

"^ftp://.*"        → ftpClient
"^smb://.*"        → smbClient
"^storage://.*"    → storageClient
```

### Services

**UrlQueueService**: URL queue management (FIFO), duplicate detection via `visited()`
**DataService**: Access result persistence, iteration

**Implementations**:
- `UrlQueueServiceImpl`, `DataServiceImpl`: In-memory (default)
- `OpenSearchDataService`: OpenSearch backend (persistent)

        private int indexToRemove = ABSENT;
        private int expectedModCount = biMap.modCount;

        // Calls to setValue on inverse entries can move already-visited entries to the end.
        // Make sure we don't visit those.
        private int remaining = biMap.size;

        private void checkForComodification() {
          if (biMap.modCount != expectedModCount) {