),
        ] = None,
        discriminator: Union[str, None] = None,
        strict: Union[bool, None] = _Unset,
        multiple_of: Union[float, None] = _Unset,
        allow_inf_nan: Union[bool, None] = _Unset,
        max_digits: Union[int, None] = _Unset,
        decimal_places: Union[int, None] = _Unset,
        examples: Optional[List[Any]] = None,
        example: Annotated[

        ),
    ] = None,
    discriminator: Annotated[
        Union[str, None],
        Doc(
            """
            Parameter field name for discriminating the type in a tagged union.
            """
        ),
    ] = None,
    strict: Annotated[
        Union[bool, None],
        Doc(
            """
            If `True`, strict validation is applied to the field.

    enemies = Sets.newHashSet("Dick", "Harry", "Tom");
  }

  public void testUnion() {
    Set<String> all = Sets.union(friends, enemies);
    assertEquals(5, all.size());

    ImmutableSet<String> immut = Sets.union(friends, enemies).immutableCopy();
    HashSet<String> mut = Sets.union(friends, enemies).copyInto(new HashSet<String>());

    enemies.add("Buck");
    assertEquals(6, all.size());

}


class Token(BaseModel):
    access_token: str
    token_type: str


class TokenData(BaseModel):
    username: Union[str, None] = None


class User(BaseModel):
    username: str
    email: Union[str, None] = None
    full_name: Union[str, None] = None
    disabled: Union[bool, None] = None


class UserInDB(User):
    hashed_password: str

}


class Token(BaseModel):
    access_token: str
    token_type: str


class TokenData(BaseModel):
    username: Union[str, None] = None


class User(BaseModel):
    username: str
    email: Union[str, None] = None
    full_name: Union[str, None] = None
    disabled: Union[bool, None] = None


class UserInDB(User):
    hashed_password: str

    headers: Optional[Dict[str, Union[Header, Reference]]] = None
    securitySchemes: Optional[Dict[str, Union[SecurityScheme, Reference]]] = None
    links: Optional[Dict[str, Union[Link, Reference]]] = None
    # Using Any for Specification Extensions
    callbacks: Optional[Dict[str, Union[Dict[str, PathItem], Reference, Any]]] = None
    pathItems: Optional[Dict[str, Union[PathItem, Reference]]] = None

    return "fakehashed" + password


oauth2_scheme = OAuth2PasswordBearer(tokenUrl="token")


class User(BaseModel):
    username: str
    email: Union[str, None] = None
    full_name: Union[str, None] = None
    disabled: Union[bool, None] = None


class UserInDB(User):
    hashed_password: str


def get_user(db, username: str):
    if username in db:
        user_dict = db[username]

!!! note "Hinweis"

            main_dict[key] = main_dict[key] + update_dict[key]
        else:
            main_dict[key] = value


def get_value_or_default(
    first_item: Union[DefaultPlaceholder, DefaultType],
    *extra_items: Union[DefaultPlaceholder, DefaultType],
) -> Union[DefaultPlaceholder, DefaultType]:
    """
    Pass items or `DefaultPlaceholder`s by descending priority.

from typing import Union

from fastapi import Cookie, Depends, FastAPI
from typing_extensions import Annotated

app = FastAPI()


def query_extractor(q: Union[str, None] = None):
    return q


def query_or_cookie_extractor(
    q: Annotated[str, Depends(query_extractor)],
    last_query: Annotated[Union[str, None], Cookie()] = None,
):
    if not q:
        return last_query
    return q


@app.get("/items/")