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## Dispatch

For synchronous calls, you bring your own thread and are responsible for managing how many simultaneous requests you make. Too many simultaneous connections wastes resources; too few harms latency.

    from docs_src.dependencies.tutorial008d import InternalError

    with pytest.raises(InternalError) as exc_info:
        client.get("/items/portal-gun")
    assert (
        exc_info.value.args[0] == "The portal gun is too dangerous to be owned by Rick"
    )


def test_internal_server_error():
    from docs_src.dependencies.tutorial008d import app

    client = TestClient(app, raise_server_exceptions=False)

* for **input** the `description` will **not be required**
* for **output** it will be **required** (and possibly `None`, or in JSON terms, `null`)

### Model for Output in Docs

You can check the output model in the docs too, **both** `name` and `description` are marked as **required** with a **red asterisk**:

<div class="screenshot">
<img src="/img/tutorial/separate-openapi-schemas/image03.png">
</div>

### Model for Input and Output in Docs

public class DefaultRootLocator implements RootLocator {

    public boolean isRootDirectory(Path dir) {
        if (Files.isDirectory(dir.resolve(".mvn"))) {
            return true;
        }
        // we're too early to use the modelProcessor ...
        Path pom = dir.resolve("pom.xml");
        try (InputStream is = Files.newInputStream(pom)) {
            XMLStreamReader parser = XMLInputFactory.newFactory().createXMLStreamReader(is);

			for k := range exp {
				if exp[k] != got[k] {
					t.Fatalf("interval %s: Expected %d values but got %d values\n", k, exp[k], got[k])
				}
			}
			// what is absent in exp is absent in got too
			for k := range got {
				if _, ok := exp[k]; !ok && got[k] > 0 {
					t.Fatalf("Unexpected interval: %s has value %d\n", k, got[k])
				}
			}
		})
	}
}

    };

    static final String[] NT_STATUS_MESSAGES = {
        "The operation completed successfully.", "Request is pending", "A notify change request is being completed.",
        "The data was too large to fit into the specified buffer.", "A device attached to the system is not functioning.", "Incorrect function.",

@app.get("/items/{item_id}")
def get_item(item_id: str, username: Annotated[str, Depends(get_username)]):
    if item_id == "portal-gun":
        raise InternalError(
            f"The portal gun is too dangerous to be owned by {username}"
        )
    if item_id != "plumbus":
        raise HTTPException(
            status_code=404, detail="Item not found, there's only a plumbus here"
        )

    "I",  # isort
    "B",  # flake8-bugbear
    "C4",  # flake8-comprehensions
    "UP",  # pyupgrade
]
ignore = [
    "E501",  # line too long, handled by black
    "B008",  # do not perform function calls in argument defaults
    "C901",  # too complex
    "W191",  # indentation contains tabs
]

[tool.ruff.lint.per-file-ignores]
"__init__.py" = ["F401"]

            .suppressing(parentBuilder.getSuppressedTests())
            .suppressing(SetCreationTester.class.getMethods())
            // BiMap.entrySet() duplicate-handling behavior is too confusing for SetCreationTester
            .withSetUp(parentBuilder.getSetUp())
            .withTearDown(parentBuilder.getTearDown())
            .createTestSuite());
    /*