*
 * @since 4.0.0
 */
@Experimental
public enum CacheRetention {
    /**
     * Data should be persisted across Maven invocations.
     * Suitable for:
     * - Dependency resolution results
     * - Compilation outputs
     * - Downloaded artifacts
     */
    PERSISTENT,

    /**
     * Data should be retained for the duration of the current Maven session.
     * Suitable for:

        with:
          python-version: "3.11"
      - name: Setup uv
        uses: astral-sh/setup-uv@v6
        with:
          version: "0.4.15"
          enable-cache: true
          cache-dependency-glob: |
            requirements**.txt
            pyproject.toml
      - name: Install Dependencies
        run: uv pip install -r requirements-github-actions.txt
      # Allow debugging with tmate

        with:
          python-version: "3.11"
      - name: Setup uv
        uses: astral-sh/setup-uv@v6
        with:
          version: "0.4.15"
          enable-cache: true
          cache-dependency-glob: |
            requirements**.txt
            pyproject.toml
      - name: Install Dependencies
        run: uv pip install -r requirements-github-actions.txt
      # Allow debugging with tmate

import static java.lang.annotation.RetentionPolicy.RUNTIME;

/**
 * Meta-annotation that marks other annotations as scope annotations.
 * <p>
 * Scopes define the lifecycle and visibility of objects in the dependency injection
 * system. Custom scope annotations should be annotated with {@code @Scope}.
 * <p>
 * Built-in scopes include:
 * <ul>
 *   <li>{@link Singleton} - One instance per container</li>

We see that we are going to need some dependencies used in several places of the application.

So we put them in their own `dependencies` module (`app/dependencies.py`).

We will now use a simple dependency to read a custom `X-Token` header:

//// tab | Python 3.9+

```Python hl_lines="3  6-8" title="app/dependencies.py"
{!> ../../docs_src/bigger_applications/app_an_py39/dependencies.py!}
```

////

 * <p>
 * This annotation can be used in conjunction with {@link Inject} to specify
 * which implementation should be injected when multiple candidates exist.
 * The value represents a unique identifier for the dependency.
 * <p>
 * Example usage:
 * <pre>
 * {@literal @}Inject
 * {@literal @}Named("mysql")
 * private Repository mysqlRepository;
 * </pre>
 *
 * @see Inject
 * @see Qualifier
 * @since 4.0.0
 */

        if (result.hasMetadataResolutionExceptions()) {
            throw result.getMetadataResolutionException(0);
        }

        // Metadata cannot be retrieved

        // Cyclic Dependency Error

        if (result.hasCircularDependencyExceptions()) {
            throw result.getCircularDependencyException(0);
        }

        // Version Range Violation

### Úsalo

Ahora puedes pasar ese `oauth2_scheme` en una dependencia con `Depends`.

{* ../../docs_src/security/tutorial001_an_py39.py hl[12] *}

Esta dependencia proporcionará un `str` que se asigna al parámetro `token` de la *path operation function*.

**FastAPI** sabrá que puede usar esta dependencia para definir un "security scheme" en el esquema OpenAPI (y en los docs automáticos del API).

import static org.junit.jupiter.api.Assertions.assertFalse;
import static org.junit.jupiter.api.Assertions.assertNotNull;
import static org.junit.jupiter.api.Assertions.assertTrue;

/**
 * A test which demonstrates maven's dependency management
 *
 */
@Deprecated
@SuppressWarnings("checkstyle:UnusedLocalVariable")
class ProjectInheritanceTest extends AbstractProjectInheritanceTestCase {

    }

    /**
     * Registers this creator with the dictionary manager upon initialization.
     * This method is annotated with {@link PostConstruct} to be executed after
     * dependency injection is complete.
     */
    @PostConstruct
    public void register() {
        if (logger.isInfoEnabled()) {
            logger.info("Load {}", this.getClass().getSimpleName());
        }