# 并发 async / await { #concurrency-and-async-await }

有关路径操作函数的 `async def` 语法以及异步代码、并发和并行的一些背景知识。

## 赶时间吗？ { #in-a-hurry }

<abbr title="too long; didn't read - 太长；没看"><strong>TL;DR:</strong></abbr>

如果你正在使用第三方库，它们会告诉你使用 `await` 关键字来调用它们，就像这样：

```Python
results = await some_library()
```

然后，通过 `async def` 声明你的 *路径操作函数*：

```Python hl_lines="2"
@app.get('/')
async def read_results():
    results = await some_library()

Detalles sobre la sintaxis `async def` para *path operation functions* y algunos antecedentes sobre el código asíncrono, la concurrencia y el paralelismo.

## ¿Con prisa? { #in-a-hurry }

<abbr title="too long; didn't read - demasiado largo; no lo leí"><strong>TL;DR:</strong></abbr>

Si estás usando paquetes de terceros que te dicen que los llames con `await`, como:

```Python
results = await some_library()
```

denial of service attacks, this setting and default was backported to Go
1.19.13, Go 1.20.8, and Go 1.21.1.

Go 1.22 made it an error for a request or response read by a net/http
client or server to have an empty Content-Length header.
This behavior is controlled by the `httplaxcontentlength` setting.

Go 1.22 changed the behavior of ServeMux to accept extended

 * in the {@link Iterators} class.
 *
 * <p><b>Java 8+ users:</b> several common uses for this class are now more comprehensively
 * addressed by the new {@link java.util.stream.Stream} library. Read the method documentation below
 * for comparisons. This class is not being deprecated, but we gently encourage you to migrate to
 * streams.
 *

* NodeController doesn't evict Pods if no Nodes are Ready ([#25571](https://github.com/kubernetes/kubernetes/pull/25571), [@gmarek](https://github.com/gmarek))

            final byte[] bomBytes = new byte[UTF8_BOM_SIZE];
            bis.mark(UTF8_BOM_SIZE);
            final int size = bis.read(bomBytes);
            if (size < 3 || !isUtf8BomBytes(bomBytes)) {
                bis.reset();
            }
            final InputSource is = new InputSource(bis);
            if (responseData.getCharSet() != null) {

   * ({@code application/xml}) is used for XML documents that are "unreadable by casual users."
   * {@link #XML_UTF_8} is provided for documents that may be read by users.
   *
   * @since 14.0
   */
  public static final MediaType APPLICATION_XML_UTF_8 = createConstantUtf8(APPLICATION_TYPE, "xml");

        },
        "dutch_keywords": {
          "type":       "keyword_marker",
          "keywords": ["hallo", "wereld", "zoeken"]
        },

        },
        "dutch_keywords": {
          "type":       "keyword_marker",
          "keywords": ["hallo", "wereld", "zoeken"]
        },

   * @since 31.0
   */
  @SafeVarargs
  public static <K, V> ImmutableMap<K, V> ofEntries(Entry<? extends K, ? extends V>... entries) {
    @SuppressWarnings("unchecked") // we will only ever read these
    Entry<K, V>[] entries2 = (Entry<K, V>[]) entries;
    return RegularImmutableMap.fromEntries(entries2);
  }

  /**