from fastapi.concurrency import (
    asynccontextmanager,
    contextmanager_in_threadpool,
)
from fastapi.dependencies.models import Dependant, SecurityRequirement
from fastapi.logger import logger
from fastapi.security.base import SecurityBase
from fastapi.security.oauth2 import OAuth2, SecurityScopes
from fastapi.security.open_id_connect_url import OpenIdConnect

!!! warning
    The recommended way to handle the *startup* and *shutdown* is using the `lifespan` parameter of the `FastAPI` app as described above. If you provide a `lifespan` parameter, `startup` and `shutdown` event handlers will no longer be called. It's all `lifespan` or all events, not both.

    You can probably skip this part.

There's an alternative way to define this logic to be executed during *startup* and during *shutdown*.

```console
// Create an env var MY_NAME in line for this program call
$ MY_NAME="Wade Wilson" python main.py

// Now it can read the environment variable

Hello Wade Wilson from Python

// The env var no longer exists afterwards
$ python main.py

Hello World from Python
```

</div>

!!! tip

from fastapi._compat import (
    PYDANTIC_V2,
    CoreSchema,
    GetJsonSchemaHandler,
    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

The `TestClient` is based on <a href="https://www.python-httpx.org" class="external-link" target="_blank">HTTPX</a>, and luckily, we can use it directly to test the API.

#### The time to answer helps the attackers

At that point, by noticing that the server took some microseconds longer to send the "Incorrect username or password" response, the attackers will know that they got _something_ right, some of the initial letters were right.

    Because Pewee doesn't play well with anything async and there are better alternatives, I won't update these docs for Pydantic v2, they are kept for now only for historical purposes.

    The examples here are no longer tested in CI (as they were before).

import logging

    request_validation_exception_handler,
    websocket_request_validation_exception_handler,
)
from fastapi.exceptions import RequestValidationError, WebSocketRequestValidationError
from fastapi.logger import logger
from fastapi.openapi.docs import (
    get_redoc_html,
    get_swagger_ui_html,
    get_swagger_ui_oauth2_redirect_html,
)
from fastapi.openapi.utils import get_openapi
from fastapi.params import Depends

        return app.openapi_schema
    openapi_schema = get_openapi(
        title="Custom title",
        version="2.5.0",
        summary="This is a very custom OpenAPI schema",
        description="Here's a longer description of the custom **OpenAPI** schema",
        routes=app.routes,
    )
    openapi_schema["info"]["x-logo"] = {
        "url": "https://fastapi.tiangolo.com/img/logo-margin/logo-teal.png"
    }