},
    default_response_class=ResponseLevel2,
    callbacks=callback_router2.routes,
    deprecated=True,
)
router2_default = APIRouter()
router4_override = APIRouter(
    prefix="/level4",
    tags=["level4a", "level4b"],
    dependencies=[Depends(dep4)],
    responses={
        404: {"description": "Client error level 4"},
        504: {"description": "Server error level 4"},
    },

   * Returns the ancestor of the current domain at the given number of levels "higher" (rightward)
   * in the subdomain list. The number of levels must be non-negative, and less than {@code N-1},
   * where {@code N} is the number of parts in the domain.
   *
   * <p>TODO: Reasonable candidate for addition to public API.
   */
  private InternetDomainName ancestor(int levels) {

    // optimistically fill index position with elements from lower levels,
    // moving the hole down. In most cases this reduces the number of
    // comparisons with toTrickle, but in some cases we will need to bubble it
    // all the way up again.
    int vacated = heap.fillHoleAt(index);
    // Try to see if toTrickle can be bubbled up min levels.
    int bubbledTo = heap.bubbleUpAlternatingLevels(vacated, toTrickle);

    // optimistically fill index position with elements from lower levels,
    // moving the hole down. In most cases this reduces the number of
    // comparisons with toTrickle, but in some cases we will need to bubble it
    // all the way up again.
    int vacated = heap.fillHoleAt(index);
    // Try to see if toTrickle can be bubbled up min levels.
    int bubbledTo = heap.bubbleUpAlternatingLevels(vacated, toTrickle);

## Team

There's a team of people that help manage and maintain the project. 😎

They have different levels of permissions and [specific instructions](./management-tasks.md).

Some of the tasks they can perform include:

* Adding labels to PRs.
* Editing PR titles.
* Adding commits on top of PRs to tweak them.

 *       <ul>
 *         <li>2 levels: average of 64ns per lock()/unlock()
 *         <li>3 levels: average of 77ns per lock()/unlock()
 *         <li>4 levels: average of 99ns per lock()/unlock()
 *         <li>5 levels: average of 103ns per lock()/unlock()
 *         <li>10 levels: average of 184ns per lock()/unlock()
 *         <li>20 levels: average of 393ns per lock()/unlock()
 *       </ul>
 * </ul>

## Dependency Injection { #dependency-injection }

Using `BackgroundTasks` also works with the dependency injection system, you can declare a parameter of type `BackgroundTasks` at multiple levels: in a *path operation function*, in a dependency (dependable), in a sub-dependency, etc.

## **FastAPI**'s `OAuth2PasswordBearer` { #fastapis-oauth2passwordbearer }

**FastAPI** provides several tools, at different levels of abstraction, to implement these security features.

In this example we are going to use **OAuth2**, with the **Password** flow, using a **Bearer** token. We do that using the `OAuth2PasswordBearer` class.

/// info

---

### 🎓 **Learning Resources for Gradle**

Kickstart your Gradle knowledge with courses, guides, and community support tailored to various experience levels:

- **[DPE University Free Courses](https://dpeuniversity.gradle.com/app/catalog)**: A collection of hands-on courses for learning Gradle, complete with project-based tasks to improve real-world skills.

All these tasks help maintain the repository.

A round of applause to them. 👏 🙇

## Team

This is the current list of team members. 😎

They have different levels of involvement and permissions, they can perform [repository management tasks](./management-tasks.md) and together we  [manage the FastAPI repository](./management.md).

<div class="user-list user-list-center">