Validator,
    lenient_issubclass,
)
from fastapi.datastructures import DefaultPlaceholder, DefaultType
from pydantic import BaseModel, create_model
from pydantic.fields import FieldInfo
from typing_extensions import Literal

if TYPE_CHECKING:  # pragma: nocover
    from .routing import APIRoute

# Cache for `create_cloned_field`
_CLONED_TYPES_CACHE: MutableMapping[
    Type[BaseModel], Type[BaseModel]
] = WeakKeyDictionary()

        model_name_map: ModelNameMap,
        field_mapping: Dict[
            Tuple[ModelField, Literal["validation", "serialization"]], JsonSchemaValue
        ],
        separate_input_output_schemas: bool = True,
    ) -> Dict[str, Any]:
        override_mode: Union[Literal["validation"], None] = (
            None if separate_input_output_schemas else "validation"
        )

    is_body_allowed_for_status_code,
)
from starlette.responses import JSONResponse
from starlette.routing import BaseRoute
from starlette.status import HTTP_422_UNPROCESSABLE_ENTITY
from typing_extensions import Literal

validation_error_definition = {
    "title": "ValidationError",
    "type": "object",
    "properties": {
        "loc": {
            "title": "Location",
            "type": "array",

    JsonSchemaValue,
    _model_rebuild,
    with_info_plain_validator_function,
)
from fastapi.logger import logger
from pydantic import AnyUrl, BaseModel, Field
from typing_extensions import Annotated, Literal, TypedDict
from typing_extensions import deprecated as typing_deprecated

try:
    import email_validator

    assert email_validator  # make autoflake ignore the unused import
    from pydantic import EmailStr

Es gibt eine Alternative, die explizit deklariert, dass ein Wert erforderlich ist. Sie können als Default das <abbr title='Zeichenfolge, die einen Wert direkt darstellt, etwa 1, "hallowelt", True, None'>Literal</abbr> `...` setzen:

=== "Python 3.9+"

    ```Python hl_lines="9"
    {!> ../../../docs_src/query_params_str_validations/tutorial006b_an_py39.py!}
    ```

=== "Python 3.8+"

E então, logo após o `yield`, descarregaremos o modelo. Esse código será executado **após** a aplicação **terminar de lidar com as requisições**, pouco antes do *encerramento*. Isso poderia, por exemplo, liberar recursos como memória ou GPU.

!!! tip "Dica"
    O `shutdown` aconteceria quando você estivesse **encerrando** a aplicação.

    Talvez você precise inicializar uma nova versão, ou apenas cansou de executá-la. 🤷

        Still, probably better to use the `Annotated` version. 😉

### Required with Ellipsis (`...`)

There's an alternative way to explicitly declare that a value is required. You can set the default to the literal value `...`:

=== "Python 3.9+"

    ```Python hl_lines="9"
    {!> ../../../docs_src/query_params_str_validations/tutorial006b_an_py39.py!}
    ```

=== "Python 3.8+"

    ```Python hl_lines="8"

And dependencies can be created in a very simple and intuitive way that allows you to just import the Python packages you need, and integrate them with your API functions in a couple of lines of code, *literally*.

You will see examples of this in the next chapters, about relational and NoSQL databases, security, etc.

## **FastAPI** compatibility