The `name` parameter is **still required** (not *optional*) because it doesn't have a default value. Still, `name` accepts `None` as the value:

```Python
say_hi(name=None)  # This works, None is valid 🎉
```

The good news is, once you are on Python 3.10 you won't have to worry about that, as you will be able to simply use `|` to define unions of types:

{* ../../docs_src/python_types/tutorial009c_py310.py hl[1,4] *}

<?xml version="1.0" encoding="UTF-8"?>
<foo xmlns:xi="http://www.w3.org/2001/XInclude">
	<xi:include href="/included.xml"/>

 *
 * <p>{@code containsKey(k)}, {@code put(k, v)} and {@code remove(k)} are all (expected and
 * amortized) constant time operations. Expected in the hashtable sense (depends on the hash
 * function doing a good job of distributing the elements to the buckets to a distribution not far
 * from uniform), and amortized since some operations can trigger a hash table resize.
 *

      // Postponed routes are always tried last. For example, if we have 2 proxies and all the
      // routes for proxy1 should be postponed, we'll move to proxy2. Only after we've exhausted
      // all the good routes will we attempt the postponed routes.
      val proxy = nextProxy()
      for (inetSocketAddress in inetSocketAddresses) {
        val route = Route(address, proxy, inetSocketAddress)

       <version>1.6.0</version>
     </dependency>
     ```

 *  New: `Cache.initialize()`. Call this on a background thread to eagerly
    initialize the response cache.
 *  New: Fold `MockWebServerRule` into `MockWebServer`. This makes it easier to
    write JUnit tests with `MockWebServer`. The `MockWebServer` library now
    depends on JUnit, though it continues to work with all testing frameworks.

  fun writerEviction() {
    val headerBlock =
      headerEntries(
        "custom-foo",
        "custom-header",
        "custom-bar",
        "custom-header",
        "custom-baz",
        "custom-header",
      )
    bytesIn.writeByte(0x40) // Literal indexed
    bytesIn.writeByte(0x0a) // Literal name (len = 10)
    bytesIn.writeUtf8("custom-foo")
    bytesIn.writeByte(0x0d) // Literal value (len = 13)

    frame.writeByte(TYPE_GOAWAY)
    frame.writeByte(FLAG_NONE)
    frame.writeInt(0) // connection-scope
    frame.writeInt(expectedStreamId) // last good stream.
    frame.writeInt(expectedError.httpCode)

    // Check writer sends the same bytes.
    assertThat(sendGoAway(expectedStreamId, expectedError, EMPTY_BYTE_ARRAY))
      .isEqualTo(frame)

        json={
            "importance": 2,
            "item": {"name": "Foo", "price": 50.5},
            "user": {"username": "Dave"},
        },
        params={"q": "somequery"},
    )
    assert response.status_code == 200
    assert response.json() == {
        "item_id": 5,
        "importance": 2,
        "item": {
            "name": "Foo",
            "price": 50.5,
            "description": None,

app.include_router(router, prefix="/{segment}")


client = TestClient(app)


def test_get():
    response = client.get("/seg/users/foo")
    assert response.status_code == 200, response.text

    assert response.status_code == 200
    assert response.json() == {"items": [{"item_id": "Foo"}, {"item_id": "Bar"}]}


def test_query_params_str_validations_q_empty_str(client: TestClient):
    response = client.get("/items/", params={"q": ""})
    assert response.status_code == 200
    assert response.json() == {"items": [{"item_id": "Foo"}, {"item_id": "Bar"}]}


def test_query_params_str_validations_q_query(client: TestClient):