///

### Étape 2 : créer une "instance" `FastAPI`

{* ../../docs_src/first_steps/tutorial001.py hl[3] *}

Ici la variable `app` sera une "instance" de la classe `FastAPI`.

Ce sera le point principal d'interaction pour créer toute votre API.

Cette `app` est la même que celle à laquelle fait référence `uvicorn` dans la commande :

<div class="termy">

```console

	// Unfreeze as soon as request context is canceled or when the function returns.
	go func() {
		<-ctx.Done()
		globalNotificationSys.ServiceFreeze(ctx, false)
	}()

	serial := r.Form.Get("serial") == "true"
	blockSizeStr := r.Form.Get("blocksize")
	fileSizeStr := r.Form.Get("filesize")

	blockSize, err := strconv.ParseUint(blockSizeStr, 10, 64)
	if err != nil {

Pendant que vous discutez avec votre crush 😍, de temps en temps vous jetez un coup d'oeil au nombre affiché au-dessus du comptoir pour savoir si c'est à votre tour d'être servis.

Jusqu'au moment où c'est (enfin) votre tour. Vous allez au comptoir, récupérez vos burgers 🍔 et revenez à votre table.

<img src="/img/async/concurrent-burgers/concurrent-burgers-06.png" class="illustration">

{* ../../docs_src/generate_clients/tutorial004.py *}

//// tab | Node.js

```Javascript
{!> ../../docs_src/generate_clients/tutorial004.js!}
```

////

Con eso, los operation IDs serían renombrados de cosas como `items-get_items` a solo `get_items`, de esa manera el generador del cliente puede generar nombres de métodos más simples.

### Generar un Cliente TypeScript con el OpenAPI Preprocesado

    first_name: str, last_name: str
```

Eso es todo.

Esas son las "anotaciones de tipos":

{* ../../docs_src/python_types/tutorial002.py hl[1] *}

Eso no es lo mismo que declarar valores predeterminados como sería con:

```Python
    first_name="john", last_name="doe"
```

Es una cosa diferente.

Estamos usando dos puntos (`:`), no igualdades (`=`).

 * "https://github.com/google/guava/wiki/ImmutableCollectionsExplained">immutable collections</a>.
 *
 * @author Jared Levy
 * @author Louis Wasserman
 * @since 2.0
 */
@GwtCompatible
@SuppressWarnings("serial") // we're overriding default serialization
public abstract class ImmutableMultiset<E> extends ImmutableCollection<E> implements Multiset<E> {

  /**

     * Includes reference counting for multi-threaded access tracking.
     */
    public static class StatsObject extends LinkedHashMap<String, Long> {
        /** Serial version UID for serialization. */
        private static final long serialVersionUID = 1L;

        /** Atomic counter for tracking reference count across multiple threads. */
        protected final AtomicInteger count;

    }

    @GwtIncompatible @J2ktIncompatible private static final long serialVersionUID = 0;
  }

  /**
   * Returns a synchronized (thread-safe) table backed by the specified table. In order to guarantee
   * serial access, it is critical that <b>all</b> access to the backing table is accomplished
   * through the returned table.
   *
   * <p>It is imperative that the user manually synchronize on the returned table when accessing any

  public static final byte DC1 = 17; // aka XON

  /**
   * Transmission On: Although originally defined as DC1, this ASCII control character is now better
   * known as the XON code used for software flow control in serial communications. The main use is
   * restarting the transmission after the communication has been stopped by the XOFF control code.
   *
   * @since 8.0
   */
  public static final byte XON = 17; // aka DC1

```Python
    first_name: str, last_name: str
```

É isso aí.

Esses são os "type hints":

{* ../../docs_src/python_types/tutorial002.py hl[1] *}

Isso não é o mesmo que declarar valores padrão como seria com:

```Python
    first_name="john", last_name="doe"
```

É uma coisa diferente.

Estamos usando dois pontos (`:`), não é igual a (`=`).