from fastapi import Depends
from typing_extensions import Annotated


async def dependency_a():
    dep_a = generate_dep_a()
    try:
        yield dep_a
    finally:
        dep_a.close()


async def dependency_b(dep_a: Annotated[DepA, Depends(dependency_a)]):
    dep_b = generate_dep_b()
    try:
        yield dep_b
    finally:
        dep_b.close(dep_a)

from typing import Annotated

from fastapi import Depends, FastAPI, HTTPException

app = FastAPI()


class InternalError(Exception):
    pass


def get_username():
    try:
        yield "Rick"
    except InternalError:
        print("Oops, we didn't raise again, Britney 😱")


@app.get("/items/{item_id}")
def get_item(item_id: str, username: Annotated[str, Depends(get_username)]):
    if item_id == "portal-gun":

    )

    # ---------------------
    context.close()
    browser.close()


process = subprocess.Popen(
    ["uvicorn", "docs_src.separate_openapi_schemas.tutorial001:app"]
)
try:
    with sync_playwright() as playwright:
        run(playwright)
finally:

    poolclass=StaticPool,
)
TestingSessionLocal = sessionmaker(autocommit=False, autoflush=False, bind=engine)


Base.metadata.create_all(bind=engine)


def override_get_db():
    try:
        db = TestingSessionLocal()
        yield db
    finally:
        db.close()


app.dependency_overrides[get_db] = override_get_db

client = TestClient(app)


def test_create_user():

from . import crud, models, schemas
from .database import SessionLocal, engine

models.Base.metadata.create_all(bind=engine)

app = FastAPI()


# Dependency
def get_db():
    db = SessionLocal()
    try:
        yield db
    finally:
        db.close()


@app.post("/users/", response_model=schemas.User)
def create_user(user: schemas.UserCreate, db: Session = Depends(get_db)):

```

!!! tip
    You can use `async` or regular functions.

    **FastAPI** will do the right thing with each, the same as with normal dependencies.

## A dependency with `yield` and `try`

If you use a `try` block in a dependency with `yield`, you'll receive any exception that was thrown when using the dependency.

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.

Common ORMs are for example: Django-ORM (part of the Django framework), SQLAlchemy ORM (part of SQLAlchemy, independent of framework) and Peewee (independent of framework), among others.

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    credentials_exception = HTTPException(
        status_code=status.HTTP_401_UNAUTHORIZED,
        detail="Could not validate credentials",
        headers={"WWW-Authenticate": "Bearer"},
    )
    try:
        payload = jwt.decode(token, SECRET_KEY, algorithms=[ALGORITHM])
        username: str = payload.get("sub")
        if username is None:
            raise credentials_exception

def check_file_field(field: ModelField) -> None:
    field_info = field.field_info
    if isinstance(field_info, params.Form):
        try:
            # __version__ is available in both multiparts, and can be mocked
            from multipart import __version__  # type: ignore

            assert __version__
            try:
                # parse_options_header is only available in the right multipart