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: `[]`.

  float: none;
}

.daterangepicker.single .drp-selected {
  display: none;
}

.daterangepicker.show-calendar .drp-calendar {
  display: block;
}

.daterangepicker.show-calendar .drp-buttons {
  display: block;
}

.daterangepicker.auto-apply .drp-buttons {
  display: none;
}

.daterangepicker .drp-calendar {
  display: none;

```

Y en Python 3.10 y superior:

```Python
q: str | None = Query(default=None)
```

...hace que el parámetro sea opcional, con un valor por defecto de `None`, lo mismo que:

```Python
q: str | None = None
```

Pero las versiones de `Query` lo declaran explícitamente como un parámetro de query.

/// info | Información

ul.has-error {
	color: #dd4b39 !important;
	list-style-type: none;
	padding: 0;
}

.form-group .has-error + .form-control {
	border-color: #dd4b39 !important;
	box-shadow: none;
}

.sidebar-mini.sidebar-collapse .sidebar-search {
	display: none !important;
}

input[type="file"].form-control:not([type="file"]) {
	height: 0% !important;
}

#result ol {
	list-style: none !important;
	padding-left: 0;
}

```Python
q: Union[str, None] = None
```

Ou como em Python 3.10 e versões superiores:

```Python
q: str | None = None
```

Por exemplo:

{* ../../docs_src/body_multiple_params/tutorial004_py310.py hl[26] *}

/// info | Informação

```Python
q: str | None = None
```

////

//// tab | Python 3.8+

```Python
q: Union[str, None] = None
```

////

Тепер ми загорнемо її у `Annotated`, і отримаємо:

//// tab | Python 3.10+

```Python
q: Annotated[str | None] = None
```

////

//// tab | Python 3.8+

```Python
q: Annotated[Union[str, None]] = None
```

////

                return "auto";
            }

            @Override
            public String getSsoType() {
                return "none";
            }
        });
        final OsddHelper osddHelper = new OsddHelper();
        osddHelper.setOsddPath("osdd/none.xml");
        osddHelper.init();
        assertFalse(osddHelper.hasOpenSearchFile());
    }

    public void test_init_disabled() {

            "axisLabel": "",
            "axisPlacement": "auto",
            "barAlignment": 0,
            "drawStyle": "line",
            "fillOpacity": 10,
            "gradientMode": "none",
            "hideFrom": {
              "legend": false,
              "tooltip": false,
              "viz": false
            },
            "insertNulls": false,
            "lineInterpolation": "linear",

`Optional[Something]` ist tatsächlich eine Abkürzung für `Union[Something, None]`, diese beiden sind äquivalent.

Das bedeutet auch, dass Sie in Python 3.10 `Something | None` verwenden können:

//// tab | Python 3.10+

```Python hl_lines="1"

						<div class="d-sm-none"></div>
						<span class="d-none d-sm-inline-block">&nbsp;</span>
						<la:message key="labels.search_result_size"
							arg0="${fe:formatFileSize(doc.content_length)}" />
					</c:if>
					<c:if test="${searchLogSupport && doc.click_count!=null && doc.click_count>0}">
						<div class="d-sm-none"></div>
						<span class="d-none d-sm-inline-block">&nbsp;</span>