assertEquals(0, queue.size());
    assertEquals(3, queue.remainingCapacity());

    assertTrue(queue.add("one"));
    assertTrue(queue.add("two"));
    assertTrue(queue.add("three"));
    assertThat(queue.element()).isEqualTo("one");
    assertThat(queue.peek()).isEqualTo("one");
    assertEquals(3, queue.size());
    assertEquals(0, queue.remainingCapacity());

    assertTrue(queue.add("four"));

Seu modelo de resposta pode ter valores padrão, como:

{* ../../docs_src/response_model/tutorial004_py310.py hl[9,11:12] *}

* `description: Union[str, None] = None` (ou `str | None = None` no Python 3.10) tem um padrão de `None`.
* `tax: float = 10.5` tem um padrão de `10.5`.
* `tags: List[str] = []` tem um padrão de uma lista vazia: `[]`.

/// note | Hinweis

FastAPI weiß, dass der Wert von `q` nicht erforderlich ist, aufgrund des definierten Defaultwertes `= None`.

Das `str | None` wird von FastAPI nicht verwendet, um zu bestimmen, dass der Wert nicht erforderlich ist. FastAPI weiß, dass er nicht erforderlich ist, weil er einen Defaultwert von `= None` hat.

### Target language

Translate to Japanese (日本語).

Language code: ja.

### Grammar and tone

- Use polite, instructional Japanese (です/ます調).
- Keep the tone concise and technical (match existing Japanese FastAPI docs).

### Headings

- Follow the existing Japanese style: short, descriptive headings (often noun phrases), e.g. 「チェック」.
- Do not add a trailing period at the end of headings.

### Quotes

				t.Errorf("#%d: %q: expected error %q; got none", i, test.input, test.error)
			}
			continue
		}
		if !strings.Contains(err.Error(), test.error) {
			t.Errorf("#%d: expected error %q; got %q", i, test.error, err)
			continue
		}
	}
}

func runBadTest(i int, test badExprTest, t *testing.T) (err error) {
	p := NewParser(nil, nil, nil) // Expression evaluation uses none of these fields of the parser.

    public void testGet() throws Exception {
        assertThat(map.get("ONE"), is("1"));
        assertThat(map.get("One"), is("1"));
        assertThat(map.get("hoge"), is(nullValue()));
    }

    /**
     * @throws Exception
     */
    @Test
    public void testPut() throws Exception {
        assertThat(map.put("One", "11"), is("1"));
        assertThat(map.get("one"), is("11"));
    }

    /**
     * @throws Exception

</div>

Cela signifie qu'il aura **toujours une valeur**, simplement, parfois la valeur pourra être `None` (ou `null` en JSON).

Cela signifie que les clients utilisant votre API n'ont pas à vérifier si la valeur existe ou non, ils peuvent **supposer que le champ sera toujours présent**, mais que, dans certains cas, il aura la valeur par défaut `None`.

E você também pode declarar parâmetros de corpo como opcionais, definindo o valor padrão com `None`:

{* ../../docs_src/body_multiple_params/tutorial001_an_py310.py hl[18:20] *}

/// note | Nota

Repare que, neste caso, o `item` que seria capturado a partir do corpo é opcional. Visto que ele possui `None` como valor padrão.

///

## Múltiplos parâmetros de corpo { #multiple-body-parameters }

首先，當然你可以自由混用 `Path`、`Query` 與請求 Body 參數的宣告，**FastAPI** 會知道該怎麼做。

你也可以將 Body 參數宣告為可選，方法是將預設值設為 `None`：

{* ../../docs_src/body_multiple_params/tutorial001_an_py310.py hl[18:20] *}

/// note | 注意

請注意，在此情況下，從 body 取得的 `item` 是可選的，因為它的預設值是 `None`。

///

## 多個 Body 參數 { #multiple-body-parameters }

在前一個範例中，路徑操作（path operation）會期望一個包含 `Item` 屬性的 JSON 主體，例如：

```JSON
{

from fastapi import FastAPI
from fastapi.openapi.docs import (
    get_redoc_html,
    get_swagger_ui_html,
    get_swagger_ui_oauth2_redirect_html,
)
from fastapi.staticfiles import StaticFiles

app = FastAPI(docs_url=None, redoc_url=None)

app.mount("/static", StaticFiles(directory="static"), name="static")


@app.get("/docs", include_in_schema=False)
async def custom_swagger_ui_html():
    return get_swagger_ui_html(