```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，再加上新的键值对：

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

你可以使用该技巧在*路径操作*中重用一些预定义响应，并把它们与额外的自定义响应组合在一起。

  @CanIgnoreReturnValue
  public final <A extends Appendable> A appendTo(
      A appendable, @Nullable Object first, @Nullable Object second, @Nullable Object... rest)
      throws IOException {
    return appendTo(appendable, iterable(first, second, rest));
  }

  /**
   * Appends the string representation of each of {@code parts}, using the previously configured

/target/
/work/
/bin/
/.settings/
.project
.classpath
*.iml
.idea
.DS_Store
dependency-reduced-pom.xml
/.serena

      implements Serializable {
    final Converter<A, B> first;
    final Converter<B, C> second;

    ConverterComposition(Converter<A, B> first, Converter<B, C> second) {
      this.first = first;
      this.second = second;
    }

    /*
     * These gymnastics are a little confusing. Basically this class has neither legacy nor

        assertThrows(IllegalStateException.class, () -> {
            Handler.setURLStreamHandlerFactory(mockFactory2); // Second call, should fail.
        }, "Setting the factory a second time should throw IllegalStateException.");
    }

    @Test
    void testOpenConnection_WithCustomFactory() throws Exception {

        int result = smbComRename.writeBytesWireFormat(dst, dstIndex);

        // Then
        assertTrue(result > 0);
        assertEquals((byte) 0x04, dst[0]); // First buffer format byte

        // Find the second buffer format byte
        int secondBufferFormatIndex = oldFileName.length() + 2; // 1 for first 0x04, 1 for null terminator
        assertEquals((byte) 0x04, dst[secondBufferFormatIndex]);
    }

    /**

   * concurrent maps whose content may change while the method is running.
   *
   * <p>The serialized output consists of the number of entries, first key, first value, second key,
   * second value, and so on.
   */
  static <K extends @Nullable Object, V extends @Nullable Object> void writeMap(
      Map<K, V> map, ObjectOutputStream stream) throws IOException {
    stream.writeInt(map.size());

    }

    @Test
    @DisplayName("Iterator with rejecting filter - finds next acceptable")
    void iteratorWithRejectingFilter() throws Exception {
        // Setup: first entry rejected, second accepted
        FileEntry entry1 = mock(FileEntry.class);
        FileEntry entry2 = mock(FileEntry.class);

        when(delegate.hasNext()).thenReturn(true, true, false);

      long burst = measureTotalTimeMillis(limiter, oneSecWorthOfWork, new Random());
      // we allow one second worth of work to go in a burst (i.e. take less than a second)
      assertThat(burst).isAtMost(1000);
      long afterBurst = measureTotalTimeMillis(limiter, oneSecWorthOfWork, new Random());
      // but work beyond that must take at least one second
      assertThat(afterBurst).isAtLeast(1000);
    }
  }

  /**

      long burst = measureTotalTimeMillis(limiter, oneSecWorthOfWork, new Random());
      // we allow one second worth of work to go in a burst (i.e. take less than a second)
      assertThat(burst).isAtMost(1000);
      long afterBurst = measureTotalTimeMillis(limiter, oneSecWorthOfWork, new Random());
      // but work beyond that must take at least one second
      assertThat(afterBurst).isAtLeast(1000);
    }
  }

  /**