from typing import Optional


def say_hi(name: Optional[str]):
    print(f"Hey {name}!")
```

`name` parametresi `Optional[str]` olarak tanımlıdır; ancak isteğe bağlı değildir, parametre olmadan fonksiyonu çağıramazsınız:

```Python
say_hi()  # Ah hayır, bu hata fırlatır! 😱
```

`name` parametresi varsayılan bir değeri olmadığı için hâlâ zorunludur (yani *optional* değildir). Yine de `name`, değer olarak `None` kabul eder:

```Python

        assertEquals("RESOLVER_WINS", ResolverType.RESOLVER_WINS.name());
        assertEquals("RESOLVER_BCAST", ResolverType.RESOLVER_BCAST.name());
        assertEquals("RESOLVER_DNS", ResolverType.RESOLVER_DNS.name());
        assertEquals("RESOLVER_LMHOSTS", ResolverType.RESOLVER_LMHOSTS.name());
    }

    /**
     * Tests the ordinal values of the enum constants.
     */
    @Test

deleted\="false" description\="Comment for getter method" enabled\="true" id\="org.eclipse.jdt.ui.text.codetemplates.gettercomment" name\="gettercomment">/**\n *\n */</template><template autoinsert\="false" context\="settercomment_context" deleted\="false" description\="Comment for setter method" enabled\="true" id\="org.eclipse.jdt.ui.text.codetemplates.settercomment" name\="settercomment">/**\n *\n */</template><template autoinsert\="true" context\="constructorcomment_context" deleted\="false" description\="Comment...

```python
from typing import Optional


def say_hi(name: Optional[str]):
    print(f"Hey {name}!")
```

O parâmetro `name` é definido como `Optional[str]`, mas não é opcional; não é possível chamar a função sem o parâmetro:

```Python
say_hi()  # Ah, não, isso gera um erro! 😱
```

O parâmetro `name` continua obrigatório (não é opcional) porque não tem valor padrão. Ainda assim, `name` aceita `None` como valor:

```Python

    // ===================================================================================
    //                                                                       Name Override
    //                                                                       =============
    @Override
    public String asTableDbName() {
        return "favorite_log";
    }

    @Override

   * multimap's key and value orderings correspond to the iteration ordering of the {@code
   * multimap.asMap()} view.
   *
   * <p>Despite the method name, this method attempts to avoid actually copying the data when it is
   * safe to do so. The exact circumstances under which a copy will or will not be performed are
   * undocumented and subject to change.
   *

        void testGetFileId() {
            assertArrayEquals(testFileId, response.getFileId());
        }

        @Test
        @DisplayName("getFileName should return the file name passed in constructor")
        void testGetFileName() {
            assertEquals(testFileName, response.getFileName());
        }
    }

    @Nested
    @DisplayName("writeBytesWireFormat Tests")

    )
    assert response.json() == {
        "name": "Fooz",
        "description": "Item description",
        "price": 3,
        "tax": 10.5,
        "tags": ["tag1", "tag2"],
    }


def test_patch_name(client: TestClient):
    response = client.patch(
        "/items/bar",
        json={"name": "Barz"},
    )
    assert response.json() == {
        "name": "Barz",
        "description": "The bartenders",

    /*
     * TODO(lowasser): consider checking for ImmutableAsList here
     * TODO(lowasser): consider checking for Multiset here
     */
    // Don't refer to ImmutableSortedSet by name so it won't pull in all that code
    if (elements instanceof ImmutableSet && !(elements instanceof SortedSet)) {
      @SuppressWarnings("unchecked") // all supported methods are covariant

    response = client.get(
        "/items?token=jessica", headers={"X-Token": "fake-super-secret-token"}
    )
    assert response.status_code == 200
    assert response.json() == {
        "plumbus": {"name": "Plumbus"},
        "gun": {"name": "Portal Gun"},
    }


def test_items_with_no_token_jessica(client: TestClient):
    response = client.get("/items", headers={"X-Token": "fake-super-secret-token"})