[Python] How to use Depends or similar thing as dependency injection outside of FastAPI...

Can anybody tell me how to use dependency injection for my get_db() outside of the FastAPI routers methods? Apparently, Depends() only covers DI in request functions.

Here's the get_db() async generator:

async def get_db() -> AsyncGenerator[AsyncSession, None]:
async with async_session() as session:
yield session


In the FastAPI router, I can simply use Depends() like this:

@router.get("/interactions", response_model=List[schemas.Interaction])
async def get_all_interactions(db: Annotated[AsyncSession, Depends(get_db)]) -> List[schemas.Interaction]:
interactions = await crud.get_interactions(db=db)

return [
schemas.Interaction.model_validate(interaction) for interaction in interactions
]


Now, outside of the request, how can I inject the get_db within a new method and get rid of async for inside of method?

@cli.command(name="create_superuser")
async def create_superuser(): # Note: how to pass db session here as param?
username = click.prompt("Username", type=str)
email = click.prompt("Email (optional)", type=str, default="")
password = getpass("Password: ")
confirm_password = getpass("Confirm Password: ")

if password != confirm_password:
click.echo("Passwords do not match")
return

async for db in database.get_db(): # Note: remove it from here
user = schemas.UserAdminCreate(
username=username,
email=None if not email else email,
password=password,
role="admin",
)
await crud.create_user(db=db, user=user)


PS: The reason for this requirement, is that, I'm going to write a test case for the create_superuser() function, which has its own database and respective session so it would be beneficial to me to inject the session db within any methods.

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