/// note

如果你不知道两者的区别，请查阅 [并发: *赶时间吗？*](../async.md#_1){.internal-link target=_blank}。

///

### 步骤 5：返回内容

{* ../../docs_src/first_steps/tutorial001.py hl[8] *}

你可以返回一个 `dict`、`list`，像 `str`、`int` 一样的单个值，等等。

你还可以返回 Pydantic 模型（稍后你将了解更多）。

还有许多其他将会自动转换为 JSON 的对象和模型（包括 ORM 对象等）。尝试下使用你最喜欢的一种，它很有可能已经被支持。

## 总结

* 导入 `FastAPI`。
* 创建一个 `app` 实例。
* 编写一个**路径操作装饰器**，如 `@app.get("/")`。

func TestCompositePrimaryKeysAssociations(t *testing.T) {
	type Label struct {
		BookID *uint  `gorm:"primarykey"`
		Name   string `gorm:"primarykey"`
		Value  string
	}

	type Book struct {
		ID     int
		Name   string
		Labels []Label
	}

	DB.Migrator().DropTable(&Label{}, &Book{})
	if err := DB.AutoMigrate(&Label{}, &Book{}); err != nil {
		t.Fatalf("failed to migrate, got %v", err)
	}

   * Data Streams</a>.
   *
   * @since 11.0
   */
  public static String getFileExtension(String fullName) {
    checkNotNull(fullName);
    String fileName = new File(fullName).getName();
    int dotIndex = fileName.lastIndexOf('.');
    return (dotIndex == -1) ? "" : fileName.substring(dotIndex + 1);
  }

  /**
   * Returns the file name without its <a

ttribute(r))&&o.setAttribute(r,i);n.head.appendChild(o).parentNode.removeChild(o)}function x(e){return null==e?e+"":"object"==typeof e||"function"==typeof e?n[i.call(e)]||"object":typeof e}var t="3.7.1",l=/HTML$/i,ce=function(e,t){return new ce.fn.init(e,t)};function c(e){var t=!!e&&"length"in e&&e.length,n=x(e);return!v(e)&&!y(e)&&("array"===n||0===t||"number"==typeof t&&0<t&&t-1 in e)}function fe(e,t){return e.nodeName&&e.nodeName.toLowerCase()===t.toLowerCase()}ce.fn=ce.prototype={jquery:t,co...

```Python hl_lines="1"
async def get_burgers(number: int):
    # Hacer algunas cosas asíncronas para crear las hamburguesas
    return burgers
```

...en lugar de `def`:

```Python hl_lines="2"
# Esto no es asíncrono
def get_sequential_burgers(number: int):
    # Hacer algunas cosas secuenciales para crear las hamburguesas
    return burgers
```

	const MaxIntermediateCAs = 10
	var (
		peerCertificates = make([]*x509.Certificate, 0, len(r.TLS.PeerCertificates))
		intermediates    *x509.CertPool
		numIntermediates int
	)
	for _, cert := range r.TLS.PeerCertificates {
		if cert.IsCA {
			numIntermediates++
			if numIntermediates > MaxIntermediateCAs {

    assertThat(log).containsExactly("red:run@100000", "blue:run@200000")
    assertThat(taskFaker.executeCallCount).isEqualTo(2)

    taskFaker.assertNoMoreTasks()
  }

  private val Int.µs: Long
    get() = this * 1_000L

  }

  @Override
  final long queryEarliestAvailable(long nowMicros) {
    return nextFreeTicketMicros;
  }

  @Override
  final long reserveEarliestAvailable(int requiredPermits, long nowMicros) {
    resync(nowMicros);
    long returnValue = nextFreeTicketMicros;
    double storedPermitsToSpend = min(requiredPermits, this.storedPermits);

{* ../../docs_src/query_params_str_validations/tutorial013_an_py39.py hl[9] *}

/// note

Keep in mind that in this case, FastAPI won't check the contents of the list.

For example, `list[int]` would check (and document) that the contents of the list are integers. But `list` alone wouldn't.

///

## Declare more metadata { #declare-more-metadata }

You can add more information about the parameter.

        @SuppressWarnings("unchecked")
        List<Plugin> plugins = (List<Plugin>) pom.getValue("build/plugins");
        int resourcesPlugin = -1;
        int customPlugin = -1;
        for (int i = 0; i < plugins.size(); i++) {
            Plugin plugin = plugins.get(i);
            if ("maven-resources-plugin".equals(plugin.getArtifactId())) {