This way, you could also have an attribute `orion_cat.owner` and the owner would contain the data for this pet's owner, taken from the table *owners*.

So, `orion_cat.owner.name` could be the name (from the `name` column in the `owners` table) of this pet's owner.

It could have a value like `"Arquilian"`.

And the ORM will do all the work to get the information from the corresponding table *owners* when you try to access it from your pet object.

    )
    pet = PetDB(name="Nibbler", owner=user)
    return pet


@app.get("/pets/", response_model=List[PetOut])
async def read_pets():
    user = UserDB(
        email="******@****.***",
        hashed_password="secrethashed",
    )
    pet1 = PetDB(name="Nibbler", owner=user)
    pet2 = PetDB(name="Zoidberg", owner=user)
    return [pet1, pet2]


client = TestClient(app)

        "name": "Firulais",
        "owner": {"name": "Foo"},
    }


def test_encode_class():
    person = Person(name="Foo")
    pet = Pet(owner=person, name="Firulais")
    assert jsonable_encoder(pet) == {"name": "Firulais", "owner": {"name": "Foo"}}
    assert jsonable_encoder(pet, include={"name"}) == {"name": "Firulais"}
    assert jsonable_encoder(pet, exclude={"owner"}) == {"name": "Firulais"}

# Codes HTTP supplémentaires

Par défaut, **FastAPI** renverra les réponses à l'aide d'une structure de données `JSONResponse`, en plaçant la réponse de votre  *chemin d'accès* à l'intérieur de cette `JSONResponse`.

Il utilisera le code HTTP par défaut ou celui que vous avez défini dans votre *chemin d'accès*.

## Codes HTTP supplémentaires

    items = relationship("Item", back_populates="owner")


class Item(Base):
    __tablename__ = "items"

    id = Column(Integer, primary_key=True)
    title = Column(String, index=True)
    description = Column(String, index=True)
    owner_id = Column(Integer, ForeignKey("users.id"))

...et **FastAPI** utilise ces mêmes déclarations pour :

* **Définir les prérequis** : depuis les paramètres de chemins des requêtes, les entêtes, les corps, les dépendances, etc.
* **Convertir des données** : depuis la requête vers les types requis.
* **Valider des données** : venant de chaque requête :
    * Générant automatiquement des **erreurs** renvoyées au client quand la donnée est invalide.
* **Documenter** l'API avec OpenAPI :

                            {"title": "Description", "type": "string"},
                        ),
                        "id": {"title": "Id", "type": "integer"},
                        "owner_id": {"title": "Owner Id", "type": "integer"},
                    },
                },
                "User": {
                    "title": "User",
                    "required": ["email", "id", "is_active"],

                            {"title": "Description", "type": "string"},
                        ),
                        "id": {"title": "Id", "type": "integer"},
                        "owner_id": {"title": "Owner Id", "type": "integer"},
                    },
                },
                "User": {
                    "title": "User",
                    "required": ["email", "id", "is_active"],

                            {"title": "Description", "type": "string"},
                        ),
                        "id": {"title": "Id", "type": "integer"},
                        "owner_id": {"title": "Owner Id", "type": "integer"},
                    },
                },
                "User": {
                    "title": "User",
                    "required": ["email", "id", "is_active"],

from pydantic import BaseModel


class ItemBase(BaseModel):
    title: str
    description: Union[str, None] = None


class ItemCreate(ItemBase):
    pass


class Item(ItemBase):
    id: int
    owner_id: int

    class Config:
        orm_mode = True


class UserBase(BaseModel):
    email: str


class UserCreate(UserBase):
    password: str


class User(UserBase):
    id: int