### 建立 `Settings` 物件 { #create-the-settings-object }

從 Pydantic 匯入 `BaseSettings` 並建立子類別，與建立 Pydantic model 的方式非常類似。

就像使用 Pydantic model 一樣，你用型別註解宣告類別屬性，並可選擇性地提供預設值。

你可以使用與 Pydantic model 相同的所有驗證功能與工具，例如不同的資料型別與透過 `Field()` 進行額外驗證。

{* ../../docs_src/settings/tutorial001_py310.py hl[2,5:8,11] *}

/// tip

如果你想要可以直接複製貼上的範例，先別用這個，請改用本文最後一個範例。

///

                    Severity.ERROR,
                    Version.BASE,
                    prefix + "systemPath",
                    d.getManagementKey(),
                    "must be omitted." + " This field may only be specified for a dependency with system scope.",
                    d);
        }

        if (request.getValidationLevel() >= ModelBuildingRequest.VALIDATION_LEVEL_MAVEN_2_0) {

 */
@NullUnmarked
public abstract class AbstractGraphTest {

  Graph<Integer> graph;

  /**
   * The same reference as {@link #graph}, except as a mutable graph. This field is null in case
   * {@link #createGraph()} didn't return a mutable graph.
   */
  MutableGraph<Integer> graphAsMutableGraph;

  static final Integer N1 = 1;
  static final Integer N2 = 2;

   * etc. -> Decoupled class loader -> Finalizer
   *
   * Now, Finalizer no longer keeps an indirect strong reference to the static
   * FinalizableReferenceQueue field in ReferenceMap. The application class loader can be reclaimed
   * at which point the Finalizer thread will stop and its decoupled class loader can also be
   * reclaimed.
   *

	if errCode != ErrUnsignedHeaders {
		t.Fatalf("Expected the APIErrorCode to %d, but got %d", ErrUnsignedHeaders, errCode)
	}

	// case where the list of signed headers doesn't contain the host field.
	signedHeaders = signedHeaders[2:5]
	// expected to fail with `ErrUnsignedHeaders`.
	_, errCode = extractSignedHeaders(signedHeaders, r)
	if errCode != ErrUnsignedHeaders {

これを行うには、`Annotated` の中で [Pydantic の `AfterValidator`](https://docs.pydantic.dev/latest/concepts/validators/#field-after-validator) を使います。

/// tip | 豆知識

Pydantic には [`BeforeValidator`](https://docs.pydantic.dev/latest/concepts/validators/#field-before-validator) などもあります。 🤓

///

```

</div>

### 创建 `Settings` 对象 { #create-the-settings-object }

从 Pydantic 导入 `BaseSettings` 并创建一个子类，这与创建 Pydantic 模型非常相似。

与 Pydantic 模型一样，用类型注解声明类属性，也可以指定默认值。

你可以使用与 Pydantic 模型相同的验证功能和工具，例如不同的数据类型，以及使用 `Field()` 进行附加验证。

{* ../../docs_src/settings/tutorial001_py310.py hl[2,5:8,11] *}

/// tip | 提示

如果你想要一个可以快速复制粘贴的示例，请不要使用这个示例，使用下面最后一个示例。

///

        }
    }

    @Test
    public void test_getDocumentExpires() {
        // Test with null config
        assertNull(crawlingInfoHelper.getDocumentExpires(null));

        // Test with documentExpires field set (fallback behavior)
        final long currentTime = 1704067200000L; // 2024-01-01 00:00:00 UTC
        ComponentUtil.register(new SystemHelper() {
            @Override
            public long getCurrentTimeAsLong() {

        CurlRequest request = new CurlRequest(Method.GET, "https://example.com");

        // Call gzip() and verify it sets compression
        request.gzip();

        // We can't directly access compression field, but we can verify the method returns this
        assertSame(request, request.gzip());
    }

    @Test
    public void testMultipleCompressionCalls() {

   * near-simultaneously) then this is the first reason known to this peer.
   */
  internal var errorCode: ErrorCode? = null
    get() = withLock { field }

  /** The exception that explains [errorCode]. Null if no exception was provided. */
  internal var errorException: IOException? = null

  init {
    if (headers != null) {