def get_client():
    app = FastAPI()
    with pytest.warns(DeprecationWarning):

        @app.get("/items/")
        async def read_items(
            q: Annotated[str | None, Query(regex="^fixedquery$")] = None,
        ):
            if q:
                return f"Hello {q}"
            else:
                return "Hello World"

    client = TestClient(app)
    return client


@needs_py310

        addBooleanOption("Xdoclint:all,-missing,-reference", true)

        // Add support for custom tags
        tags("apiNote:a:API Note:", "implSpec:a:Implementation Requirements:", "implNote:a:Implementation Note:")

        // Process all source files for valid javadoc, not just public ones
        addBooleanOption("private", true)
        addBooleanOption("package", true)
    }

   * {@code SerializableTester} calls with other, GWT-compatible tests.
   *
   * <p>Note that the specified object may not be known by the compiler to be a {@link
   * java.io.Serializable} instance, and is thus declared an {@code Object}. For example, it might
   * be declared as a {@code List}.
   *
   * <p>Note also that serialization is not in general required to return an object that is

        "instance": "localhost:9000",
        "job": "minio-job-node",
        "pool": "0",
        "server": "127.0.0.1:9000",
        "set": "0",
        "severity": "critical"
      },
      "annotations": {
        "description": "MinIO instance 127.0.0.1:9000 of job minio-job has tolerance <=0 for more than 5 minutes.",
        "summary": "Instance 127.0.0.1:9000 unable to tolerate node failures"
      },

	//	}
	NOP	F2

	//	LNOP ',' rreg // asm doesn't support the leading comma.
	//	{
	//		outcode(int($1), &nullgen, 0, &$3);
	//	}
	NOP	R2

	//	LNOP ',' freg // asm doesn't support the leading comma.
	//	{
	//		outcode(int($1), &nullgen, 0, &$3);
	//	}
	NOP	F2

	//	LNOP imm
	//	{
	//		outcode(int($1), &$2, 0, &nullgen);
	//	}
	NOP	$4

	//
	// special

  // +optional
  optional k8s.io.api.core.v1.ObjectReference related = 9;

  // note is a human-readable description of the status of this operation.
  // Maximal length of the note is 1kB, but libraries should be prepared to
  // handle values up to 64kB.
  // +optional
  optional string note = 10;

  // type is the type of this event (Normal, Warning), new types could be added in the future.

app = FastAPI()


def write_log(message: str):
    with open("log.txt", mode="a") as log:
        log.write(message)


def get_query(background_tasks: BackgroundTasks, q: str | None = None):
    if q:
        message = f"found query: {q}\n"
        background_tasks.add_task(write_log, message)
    return q


@app.post("/send-notification/{email}")
async def send_notification(

</div>

Isso significa que ele **sempre terá um valor**, só que às vezes o valor pode ser `None` (ou `null` em termos de JSON).

Isso quer dizer que, os clientes que usam sua API não precisam verificar se o valor existe ou não, eles podem **assumir que o campo sempre estará lá**, mas que em alguns casos terá o valor padrão de `None`.

A maneira de descrever isso no OpenAPI é marcar esse campo como **obrigatório**, porque ele sempre estará lá.

    client = TestClient(app)
    return client


@needs_py310
@pytest.mark.parametrize(
    "path,headers,expected_status,expected_response",
    [
        ("/items", None, 200, {"X-Token values": None}),
        ("/items", {"x-token": "foo"}, 200, {"X-Token values": ["foo"]}),
        # TODO: fix this, is it a bug?

import javax.xml.transform.stream.StreamResult
import org.w3c.dom.Document
import org.w3c.dom.Element
import org.w3c.dom.Node

class XIncludeAwareXmlProvider {

    Document root

    Element parse(File sourceFile) {
        root = parseSourceFile(sourceFile)
        root.documentElement
    }

    Node emptyDoc() {
        root = DocumentBuilderFactory.newInstance().newDocumentBuilder().newDocument()
    }