{!../../docs_src/first_steps/tutorial001.py!}
```

C'est une fonction Python.

Elle sera appelée par **FastAPI** quand une requête sur l'URL `/` sera reçue via une opération `GET`.

Ici, c'est une fonction asynchrone (définie avec `async def`).

---

Vous pourriez aussi la définir comme une fonction classique plutôt qu'avec `async def` :

```Python hl_lines="7"
{!../../docs_src/first_steps/tutorial003.py!}
```

### Locks

We have 3 different things that we synchronize on.

#### Http2Connection

          @SuppressWarnings("ThreadPriorityCheck") // doing our best to test for races
          public Boolean get() {
            // Check that this method is called exactly once, by the first
            // thread to synchronize.
            long t0 = System.nanoTime();
            while (waitingThreads() != numThreads - 1) {
              if (System.nanoTime() - t0 > timeout) {
                thrown.set(

          @SuppressWarnings("ThreadPriorityCheck") // doing our best to test for races
          public Boolean get() {
            // Check that this method is called exactly once, by the first
            // thread to synchronize.
            long t0 = System.nanoTime();
            while (waitingThreads() != numThreads - 1) {
              if (System.nanoTime() - t0 > timeout) {
                thrown.set(

  //
  // Socket reads are unguarded but are only made by the reader thread.
  //
  // Certain operations (like SYN_STREAM) need to synchronize on both the frameWriter (to do
  // blocking I/O) and this (to create streams). Such operations must synchronize on 'this' last.
  // This ensures that we never wait for a blocking operation while holding 'this'.

  /** True if this peer initiated the connection. */

			finished: func(errs []error) {
				if countErrs(errs, nil) != len(errs) {
					retErr = fmt.Errorf("one or more errors reported during listing: %v", errors.Join(errs...))
				}
			},
		})
		jt.Wait() // synchronize all the concurrent heal jobs
		if err != nil {
			// Set this such that when we return this function
			// we let the caller retry this disk again for the
			// buckets it failed to list.
			retErr = err
		}

name: build

on:
  push:
    branches:
      - master
  pull_request:
    types: [opened, labeled, unlabeled, synchronize]

permissions:
  contents: read

env:
  GRADLE_OPTS: "-Dorg.gradle.jvmargs=-Xmx4g -Dorg.gradle.daemon=false -Dkotlin.incremental=false"

jobs:
  publish:
    runs-on: ubuntu-latest
    if: github.repository == 'square/okhttp' && github.ref == 'refs/heads/master'

    steps:
      - name: Checkout

     * </ul>
     *
     * All the states where thread != currentThread are identical for our purposes, and so even
     * though it's racy, we don't care which of those values we get, so no need to synchronize.
     */
    @CheckForNull @LazyInit Thread thread;

    /** Only used by the thread associated with this object */
    @CheckForNull Runnable nextTask;

    }


    @Override
    public void run () {
        Thread run_thread = Thread.currentThread();
        Exception ex0 = null;

        try {
            /*
             * We cannot synchronize (run_thread) here or the caller's
             * thread.wait( timeout ) cannot reaquire the lock and
             * return which would render the timeout effectively useless.
             */

## Installation

<div class="termy">

```console
$ pip install fastapi

---> 100%
```

</div>