```

Це означає, що `item` може бути `int` або `str`.

#### Можливо `None` { #possibly-none }

Ви можете оголосити, що значення може мати тип, наприклад `str`, але також може бути `None`.

//// tab | Python 3.10+

```Python hl_lines="1"
{!> ../../docs_src/python_types/tutorial009_py310.py!}
```

////

app = FastAPI()


class Item(BaseModel):
    name: str
    price: float
    is_offer: bool | None = None


@app.get("/")
def read_root():
    return {"Hello": "World"}


@app.get("/items/{item_id}")
def read_item(item_id: int, q: str | None = None):
    return {"item_id": item_id, "q": q}


@app.put("/items/{item_id}")
def update_item(item_id: int, item: Item):

     * Gets the installation Toolchains source.
     *
     * @return the installation Toolchains source or {@code null} if none
     */
    @Nonnull
    Optional<Source> getInstallationToolchainsSource();

    /**
     * Gets the user Toolchains source.
     *
     * @return the user Toolchains source or {@code null} if none
     */
    @Nonnull
    Optional<Source> getUserToolchainsSource();

    @Nonnull

    /**
     * Locates the pom in the given directory.
     *
     * @param dir the directory to locate the pom for, never {@code null}
     * @return a {@code Source} pointing to the located pom or an empty {@code Optional} if none was found by this parser
     */
    @Nonnull
    Optional<Source> locate(@Nonnull Path dir);

    /**
     * Parse the model obtained previously by a previous call to {@link #locate(Path)}.
     *

                DependencyScope.TEST.isTransitive(),
                byProjectPath(CommonBuilds.PROJECT_PATH_TEST)));
        result.add(internalScopeManager.createDependencyScope(
                DependencyScope.NONE.id(), DependencyScope.NONE.isTransitive(), Collections.emptySet()));
        result.add(internalScopeManager.createDependencyScope(
                DependencyScope.COMPILE_ONLY.id(),
                DependencyScope.COMPILE_ONLY.isTransitive(),

# Format: RequestType { scope:SCOPE ref:REFERENCE_TYPE }
#
# SCOPE OPTIONS:
#   session - Cache for entire Maven session (all modules in multi-module build)
#   request - Cache only for current request + its child requests
#   none    - Disable caching entirely
#
# REFERENCE OPTIONS:
#   hard - Strong reference (stays in memory, faster access)
#   soft - Weak reference (can be garbage collected under memory pressure)
#
# CONFIGURATION BREAKDOWN:

    assert response.status_code == 200
    assert response.json() == {
        "item_id": 5,
        "item": {"name": "Foo", "price": 3.0, "description": None, "tax": None},
    }


def test_items_6(client: TestClient):
    response = client.put(
        "/items/6",
        json={
            "item": {
                "name": "Bar",
                "price": 0.2,

from fastapi import FastAPI

app = FastAPI(docs_url="/documentation", redoc_url=None)


@app.get("/items/")
async def read_items():

`Field(primary_key=True)` tells SQLModel that the `id` is the **primary key** in the SQL database (you can learn more about SQL primary keys in the SQLModel docs).

    **Note:** We use `int | None` for the primary key field so that in Python code we can *create an object without an `id`* (`id=None`), assuming the database will *generate it when saving*. SQLModel understands that the database will provide the `id` and *defines the column as a non-null `INTEGER`* in the database schema. See [SQLModel...

`id` der **Primärschlüssel** in der SQL-Datenbank ist (Sie können mehr über SQL-Primärschlüssel in der SQLModel-Dokumentation erfahren).

    **Hinweis:** Wir verwenden für das Primärschlüsselfeld `int | None`, damit wir im Python-Code *ein Objekt ohne `id` erstellen* können (`id=None`), in der Annahme, dass die Datenbank sie *beim Speichern generiert*. SQLModel versteht, dass die Datenbank die `id` bereitstellt, und *definiert die Spalte im Datenbankschema als ein Nicht-Null-`INTEGER`*. Siehe...