? newHashSet(asList(elements).subList(1, size))
                            : Sets.<String>newHashSet();
                    return Sets.union(set1, set2);
                  }
                })
            .named("Sets.union")
            .withFeatures(CollectionSize.ANY, CollectionFeature.ALLOWS_NULL_VALUES)
            .createTestSuite());

    suite.addTest(

* ✍ `app` 📁 & ⛔ ⚫️.
* ✍ 🛁 📁 `__init__.py`.
* ✍ `main.py` 📁 ⏮️:

```Python
from typing import Union

from fastapi import FastAPI

app = FastAPI()


@app.get("/")
def read_root():
    return {"Hello": "World"}


@app.get("/items/{item_id}")
def read_item(item_id: int, q: Union[str, None] = None):
    return {"item_id": item_id, "q": q}
```

### 📁

      "Licensor" shall mean the copyright owner or entity authorized by
      the copyright owner that is granting the License.

      "Legal Entity" shall mean the union of the acting entity and all
      other entities that control, are controlled by, or are under common
      control with that entity. For the purposes of this definition,

## 响应模型编码参数

你的响应模型可以具有默认值，例如：

```Python hl_lines="11  13-14"
{!../../docs_src/response_model/tutorial004.py!}
```

* `description: Union[str, None] = None` 具有默认值 `None`。
* `tax: float = 10.5` 具有默认值 `10.5`.
* `tags: List[str] = []` 具有一个空列表作为默认值： `[]`.

但如果它们并没有存储实际的值，你可能想从结果中忽略它们的默认值。

举个例子，当你在 NoSQL 数据库中保存了具有许多可选属性的模型，但你又不想发送充满默认值的很长的 JSON 响应。

            }
        }
        public void decode(NdrBuffer _src) throws NdrException {
            _src.align(4);
            level = (int)_src.dec_ndr_long();
            _src.dec_ndr_long(); /* union discriminant */
            int _ep = _src.dec_ndr_long();

            if (_ep != 0) {
                if (e == null) { /* YOYOYO */
                    e = new DfsEnumArray1();
                }

      "Licensor" shall mean the copyright owner or entity authorized by
      the copyright owner that is granting the License.

      "Legal Entity" shall mean the union of the acting entity and all
      other entities that control, are controlled by, or are under common
      control with that entity. For the purposes of this definition,

      "Licensor" shall mean the copyright owner or entity authorized by
      the copyright owner that is granting the License.

      "Legal Entity" shall mean the union of the acting entity and all
      other entities that control, are controlled by, or are under common
      control with that entity. For the purposes of this definition,

      "Licensor" shall mean the copyright owner or entity authorized by
      the copyright owner that is granting the License.

      "Legal Entity" shall mean the union of the acting entity and all
      other entities that control, are controlled by, or are under common
      control with that entity. For the purposes of this definition,

	}
	if len(usersList) != 1 {
		c.Fatalf("expected user listing output: %v", usersList)
	}
	uinfo := usersList[userDN]
	if uinfo.PolicyName != policy || uinfo.Status != madmin.AccountEnabled {
		c.Fatalf("expected user listing content: %v", uinfo)
	}

	// Validate that the client from sts creds can access the bucket.
	c.mustListObjects(ctx, minioClient, bucket)

```

### Exemplo na UI da documentação

Com qualquer um dos métodos acima, os `/docs` vão ficar assim:

<img src="/img/tutorial/body-fields/image01.png">

### `Body` com vários `examples`

Alternativamente ao único `example`, você pode passar `examples` usando um `dict` com **vários examples**, cada um com informações extras que serão adicionadas no **OpenAPI** também.

As chaves do `dict` identificam cada exemplo, e cada valor é outro `dict`.