pwd_context = CryptContext(schemes=["bcrypt"], deprecated="auto")

oauth2_scheme = OAuth2PasswordBearer(tokenUrl="token")

app = FastAPI()


def verify_password(plain_password, hashed_password):
    return pwd_context.verify(plain_password, hashed_password)


def get_password_hash(password):
    return pwd_context.hash(password)


def get_user(db, username: str):
    if username in db:

                    "operationId": "main__get",
                    "responses": {
                        "200": {
                            "description": "Successful Response",
                            "content": {"text/plain": {"schema": {"type": "string"}}},
                        }
                    },
                }
            }
        },

            data={"token": "foo"},
            files={"file": filea, "fileb": ("testb.txt", fileb, "text/plain")},
        )
    assert response.status_code == 200, response.text
    assert response.json() == {
        "file_size": 14,
        "token": "foo",
        "fileb_content_type": "text/plain",
    }


@needs_py39
def test_openapi_schema(client: TestClient):

### Override the `HTTPException` error handler

The same way, you can override the `HTTPException` handler.

For example, you could want to return a plain text response instead of JSON for these errors:

```Python hl_lines="3-4  9-11  22"
{!../../../docs_src/handling_errors/tutorial004.py!}
```

!!! note "Technical Details"

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

```

### `HTMLResponse`

Takes some text or bytes and returns an HTML response, as you read above.

### `PlainTextResponse`

Takes some text or bytes and returns an plain text response.

```Python hl_lines="2  7  9"
{!../../../docs_src/custom_response/tutorial005.py!}
```

### `JSONResponse`

Takes some data and returns an `application/json` encoded response.

    title: Building a CRUD API with FastAPI and Supabase
  - author: Adejumo Ridwan Suleiman
    author_link: https://www.linkedin.com/in/adejumoridwan/
    link: https://medium.com/python-in-plain-english/build-an-sms-spam-classifier-serverless-database-with-faunadb-and-fastapi-23dbb275bc5b
    title: Build an SMS Spam Classifier Serverless Database with FaunaDB and FastAPI
  - author: Raf Rasenberg

instead of being called directly (as it would block the server).

If you are coming from another async framework that does not work in the way described above and you are used to defining trivial compute-only *path operation functions* with plain `def` for a tiny performance gain (about 100 nanoseconds), please note that in **FastAPI** the effect would be quite opposite. In these cases, it's better to use `async def` unless your *path operation functions* use code that performs blocking <abbr...

                </mxCell>
                <mxCell id="85" value="&lt;span style=&quot;font-family: &amp;#34;roboto&amp;#34; ; font-size: 24px&quot;&gt;Plain response from: someapp.example.com&lt;/span&gt;" style="shape=hexagon;perimeter=hexagonPerimeter2;whiteSpace=wrap;html=1;fixedSize=1;strokeColor=#9673a6;strokeWidth=3;fillColor=#e1d5e7;" parent="1" vertex="1">

pwd_context = CryptContext(schemes=["bcrypt"], deprecated="auto")

oauth2_scheme = OAuth2PasswordBearer(tokenUrl="token")

app = FastAPI()


def verify_password(plain_password, hashed_password):
    return pwd_context.verify(plain_password, hashed_password)


def get_password_hash(password):
    return pwd_context.hash(password)


def get_user(db, username: str):
    if username in db: