* This communicates to your callers all of the semantic guarantees listed above, which is almost
 * always very useful information.
 *
 * <p>On the other hand, a <i>parameter</i> type of {@link ImmutableList} is generally a nuisance to
 * callers. Instead, accept {@link Iterable} and have your method or constructor body pass it to the
 * appropriate {@code copyOf} method itself.
 *

## Controllers

Istiod consists of a collection of controllers. Per Kubernetes, "controllers are control loops that watch the state of your cluster, then make or request changes where needed."

        4,
        "four");
    assertMapEquals(
        ImmutableBiMap.of("one", 1, "two", 2, "three", 3, "four", 4, "five", 5),
        "one",
        1,
        "two",
        2,
        "three",
        3,
        "four",
        4,
        "five",
        5);
    assertMapEquals(
        ImmutableBiMap.of("one", 1, "two", 2, "three", 3, "four", 4, "five", 5).inverse(),
        1,
        "one",

      // We check the state after adding the listener as a way to ensure that our listener was added
      // to a NEW service.
      checkArgument(service.state() == NEW, "Can only manage NEW services, %s", service);
    }
    // We have installed all of our listeners and after this point any state transition should be
    // correct.
    this.state.markReady();
  }

  /**

      // We check the state after adding the listener as a way to ensure that our listener was added
      // to a NEW service.
      checkArgument(service.state() == NEW, "Can only manage NEW services, %s", service);
    }
    // We have installed all of our listeners and after this point any state transition should be
    // correct.
    this.state.markReady();
  }

  /**

## Pin your `fastapi` version

The first thing you should do is to "pin" the version of **FastAPI** you are using to the specific latest version that you know works correctly for your application.

For example, let's say you are using version `0.112.0` in your app.

If you use a `requirements.txt` file you could specify the version with:

 * 
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 * 
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

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Utilisez les types Python standard pour tous les attributs :

{* ../../docs_src/body/tutorial001.py hl[7:11] *}

Tout comme pour la déclaration de paramètres de requête, quand un attribut de modèle a une valeur par défaut, il n'est pas nécessaire. Sinon, cet attribut doit être renseigné dans le corps de la requête. Pour rendre ce champ optionnel simplement, utilisez `None` comme valeur par défaut.

## What is "Dependency Injection"

**"Dependency Injection"** means, in programming, that there is a way for your code (in this case, your *path operation functions*) to declare things that it requires to work and use: "dependencies".

And then, that system (in this case **FastAPI**) will take care of doing whatever is needed to provide your code with those needed dependencies ("inject" the dependencies).

This is very useful when you need to: