app = FastAPI()


class BaseItem(BaseModel):
    description: str
    type: str


class CarItem(BaseItem):
    type: str = "car"


class PlaneItem(BaseItem):
    type: str = "plane"
    size: int


items = {
    "item1": {"description": "All my friends drive a low rider", "type": "car"},
    "item2": {
        "description": "Music is my aeroplane, it's my aeroplane",
        "type": "plane",

        // Verify field accessibility is restored to its original state
        boolean finalAccessibility = field.canAccess(bean);
        assertEquals(
                initialAccessibility,
                finalAccessibility,
                "Field accessibility should be restored to its original state after setting value");
    }

    @Test

import java.nio.file.Files;
import java.util.Map;
import java.util.Objects;

import org.apache.maven.settings.Settings;
import org.apache.maven.settings.v4.SettingsStaxWriter;

/**
 * Handles serialization of settings into the default textual format.
 *
 * @deprecated since 4.0.0, use {@link SettingsStaxWriter} instead
 */
@Named
@Singleton
@Deprecated(since = "4.0.0")
public class DefaultSettingsWriter implements SettingsWriter {

    /**
     * <b>Warning</b>: ignored (always return <code>0 == Logger.LEVEL_DEBUG</code>).
     */
    @Override
    public int getThreshold() {
        return 0;
    }

    /**
     * <b>Warning</b>: ignored.
     */
    @Override
    public void setThreshold(int threshold) {}

    /**
     * <b>Warning</b>: ignored (always return <code>null</code>).
     */
    @Override

        int buildNumber = metadata.metadata.getVersioning().getSnapshot().getBuildNumber();
        assertEquals(1, buildNumber);
    }

    @Test
    void buildNumberSet() {
        RemoteSnapshotMetadata metadata =
                new RemoteSnapshotMetadata(new DefaultArtifact("a:b:1-SNAPSHOT"), new Date(), 42);
        metadata.merge(new Metadata());

				"name": "my name",
			},
			expect: clause.Values{
				Columns: []clause.Column{{Name: "name"}},
				Values:  [][]interface{}{{"my name"}},
			},
		},
		{
			name: "Test convert int value",
			input: map[string]interface{}{
				"age": 18,
			},
			expect: clause.Values{
				Columns: []clause.Column{{Name: "age"}},
				Values:  [][]interface{}{{18}},
			},
		},
		{

<div class="termy">

```console
// Go to the home directory
$ cd
// Create a directory for all your code projects
$ mkdir code
// Enter into that code directory
$ cd code
// Create a directory for this project
$ mkdir awesome-project
// Enter into that project directory
$ cd awesome-project
```

</div>

## Create a Virtual Environment { #create-a-virtual-environment }

        return custom_route_handler


app = FastAPI()
app.router.route_class = ValidationErrorLoggingRoute


@app.post("/")
async def sum_numbers(numbers: Annotated[list[int], Body()]):

---

其他有用的场景是当你想要接收其他类型的键时，例如 `int`。

这也是我们在接下来将看到的。

在下面的例子中，你将接受任意键为 `int` 类型并且值为 `float` 类型的 `dict`：

{* ../../docs_src/body_nested_models/tutorial009_py39.py hl[7] *}

/// tip

请记住 JSON 仅支持将 `str` 作为键。

但是 Pydantic 具有自动转换数据的功能。

这意味着，即使你的 API 客户端只能将字符串作为键发送，只要这些字符串内容仅包含整数，Pydantic 就会对其进行转换并校验。

然后你接收的名为 `weights` 的 `dict` 实际上将具有 `int` 类型的键和 `float` 类型的值。

///

## 总结

class Item(BaseModel):
    name: str
    description: str | None = None
    price: float
    tax: float | None = None


@app.put("/items/{item_id}")
async def update_item(
    *,
    item_id: int,
    item: Item = Body(
        openapi_examples={
            "normal": {
                "summary": "A normal example",
                "description": "A **normal** item works correctly.",
                "value": {