'Whitelist' validation step. The parameter field will be the single one
            allowed by the alias or set of aliases defined.
            """
        ),
    ] = None,
    serialization_alias: Annotated[
        Union[str, None],
        Doc(
            """
            'Blacklist' validation step. The vanilla parameter field will be the
            single one of the alias' or set of aliases' fields and all the other

                be `None`.

                This is useful when you want to have optional authentication.

                It is also useful when you want to have authentication that can be
                provided in one of multiple optional ways (for example, in HTTP Basic
                authentication or in an HTTP Bearer token).
                """
            ),
        ] = True,
    ):

                },
            ]
        }
    )


def test_get_invalid_one_header_items():
    response = client.get("/items/", headers={"X-Token": "invalid"})
    assert response.status_code == 400, response.text
    assert response.json() == {"detail": "X-Token header invalid"}


def test_get_invalid_one_users():
    response = client.get("/users/", headers={"X-Token": "invalid"})

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

    The first one to _not_ be a `DefaultPlaceholder` will be returned.

    Otherwise, the first item (a `DefaultPlaceholder`) will be returned.
    """
    items = (first_item,) + extra_items
    for item in items:

                `None`.

                This is useful when you want to have optional authentication.

                It is also useful when you want to have authentication that can be
                provided in one of multiple optional ways (for example, in a query
                parameter or in an HTTP Bearer token).
                """
            ),
        ] = True,
    ):
        self.model: APIKey = APIKey(

            ]
        }
    )


@needs_py39
def test_get_invalid_one_header_items(client: TestClient):
    response = client.get("/items/", headers={"X-Token": "invalid"})
    assert response.status_code == 400, response.text
    assert response.json() == {"detail": "X-Token header invalid"}


@needs_py39
def test_get_invalid_one_users(client: TestClient):

                    "msg": "field required",
                    "type": "value_error.missing",
                },
            ]
        }
    )


@needs_py39
def test_get_invalid_one_header(client: TestClient):
    response = client.get("/items/", headers={"X-Token": "invalid"})
    assert response.status_code == 400, response.text
    assert response.json() == {"detail": "X-Token header invalid"}

    if origin is Union or origin is UnionType:
        at_least_one_scalar_sequence = False
        for arg in get_args(annotation):
            if field_annotation_is_scalar_sequence(arg):
                at_least_one_scalar_sequence = True
                continue
            elif not field_annotation_is_scalar(arg):
                return False
        return at_least_one_scalar_sequence

                },
            ]
        }
    )


def test_get_invalid_one_header_items():
    response = client.get("/items/", headers={"X-Token": "invalid"})
    assert response.status_code == 400, response.text
    assert response.json() == {"detail": "X-Token header invalid"}


def test_get_invalid_one_users():
    response = client.get("/users/", headers={"X-Token": "invalid"})

                    "msg": "field required",
                    "type": "value_error.missing",
                },
            ]
        }
    )


def test_get_invalid_one_header():
    response = client.get("/items/", headers={"X-Token": "invalid"})
    assert response.status_code == 400, response.text
    assert response.json() == {"detail": "X-Token header invalid"}