```Python
old_dict = {
    "old key": "old value",
    "second old key": "second old value",
}
new_dict = {**old_dict, "new key": "new value"}
```

Aqui, o `new_dict` terá todos os pares de chave-valor do `old_dict` mais o novo par de chave-valor:

```Python
{
    "old key": "old value",
    "second old key": "second old value",
    "new key": "new value",
}
```

对于这些情况，你可以使用Python的技术，将 `dict` 与 `**dict_to_unpack` 解包：
```Python
old_dict = {
    "old key": "old value",
    "second old key": "second old value",
}
new_dict = {**old_dict, "new key": "new value"}
```

这里， new_dict 将包含来自 old_dict 的所有键值对加上新的键值对：
```python
{
    "old key": "old value",
    "second old key": "second old value",
    "new key": "new value",
}
```
您可以使用该技术在路径操作中重用一些预定义的响应，并将它们与其他自定义响应相结合。

 *   <li>Old document deletion after successful crawling</li>
 *   <li>Crawling execution monitoring and timing</li>
 * </ul>
 */
public class DataIndexHelper {

    /** Logger instance for this class */
    private static final Logger logger = LogManager.getLogger(DataIndexHelper.class);

    /** Parameter key for controlling deletion of old documents */

    }

    @Test
    @DisplayName("Test automatic cleanup of old resources")
    @Timeout(value = 5, unit = TimeUnit.SECONDS)
    void testAutomaticCleanup() throws InterruptedException {
        // Configure with very short max age for testing
        resourceManager.configure(100, 50, true, true);

        TestResource resource = new TestResource("old");
        resourceManager.registerResource(resource);

  wget "http://old-releases.ubuntu.com/ubuntu/pool/main/e/eglibc/libc6_2.12.1-0ubuntu6_amd64.deb" && \
      unar "libc6_2.12.1-0ubuntu6_amd64.deb" && \
      tar -C "${TARGET}" -xvzf "libc6_2.12.1-0ubuntu6_amd64/data.tar.gz" && \
      rm -rf "libc6_2.12.1-0ubuntu6_amd64.deb" "libc6_2.12.1-0ubuntu6_amd64"
  # Download binary glibc 2.12 development library release.

    int originalCount = getMultiset().count(e0());
    assertEquals("old count", originalCount, getMultiset().remove(e0(), 0));
    expectUnchanged();
  }

  @CollectionSize.Require(absent = ZERO)
  @CollectionFeature.Require(SUPPORTS_REMOVE)
  public void testRemove_occurrences_present() {
    assertEquals(
        "multiset.remove(present, 2) didn't return the old count",
        1,
        getMultiset().remove(e0(), 2));

    int originalCount = getMultiset().count(e0());
    assertEquals("old count", originalCount, getMultiset().remove(e0(), 0));
    expectUnchanged();
  }

  @CollectionSize.Require(absent = ZERO)
  @CollectionFeature.Require(SUPPORTS_REMOVE)
  public void testRemove_occurrences_present() {
    assertEquals(
        "multiset.remove(present, 2) didn't return the old count",
        1,
        getMultiset().remove(e0(), 2));

    int originalCount = getMultiset().count(e0());
    assertEquals("old count", originalCount, getMultiset().add(e0(), 0));
    expectUnchanged();
  }

  @CollectionFeature.Require(SUPPORTS_ADD)
  public void testAddOccurrences() {
    int originalCount = getMultiset().count(e0());
    assertEquals("old count", originalCount, getMultiset().add(e0(), 2));
    assertEquals("old count", originalCount + 2, getMultiset().count(e0()));
  }

    int originalCount = getMultiset().count(e0());
    assertEquals("old count", originalCount, getMultiset().add(e0(), 0));
    expectUnchanged();
  }

  @CollectionFeature.Require(SUPPORTS_ADD)
  public void testAddOccurrences() {
    int originalCount = getMultiset().count(e0());
    assertEquals("old count", originalCount, getMultiset().add(e0(), 2));
    assertEquals("old count", originalCount + 2, getMultiset().count(e0()));
  }

    }

    /**
     * Deletes old documents that have the same URL but different document IDs
     * as the documents in the provided list. This prevents duplicate documents
     * from accumulating in the index.
     *
     * @param searchEngineClient the search engine client to use for deletion
     * @param docList the list of new documents to check against
     * @return the number of old documents that were deleted
     */