def test_discriminator_pydantic_v2() -> None:
    from pydantic import Tag

    app = FastAPI()

    class FirstItem(BaseModel):
        value: Literal["first"]
        price: int

    class OtherItem(BaseModel):
        value: Literal["other"]
        price: float

    Item = Annotated[
        Union[Annotated[FirstItem, Tag("first")], Annotated[OtherItem, Tag("other")]],
        Field(discriminator="value"),
    ]