So:

```Python
q: Union[str, None] = Query(default=None)
```

...makes the parameter optional, with a default value of `None`, the same as:

```Python
q: Union[str, None] = None
```

And in Python 3.10 and above:

```Python
q: str | None = Query(default=None)
```

...makes the parameter optional, with a default value of `None`, the same as:

```Python

   * loaded by this test and that will obviously remain loaded for as long as the test is running.
   * So in order to check ClassLoader garbage collection we need to create a new ClassLoader and
   * make it load its own version of FinalizableReferenceQueue. Then we need to interact with that
   * parallel version through reflection in order to exercise the parallel

		can extract a pod uid from it.
		if we can, open the netns, and save a map of uid->netns-fd
	*/

	podUIDNetns := make(PodToNetns)
	netnsObserved := sets.New[uint64]()

	entries, err := fs.ReadDir(p.proc, ".")
	if err != nil {
		return nil, err
	}

	desiredUIDs := sets.New(maps.Keys(pods)...)
	for _, entry := range entries {
		// we can't break here because we need to close all the netns we opened

     *
     * - a call that consults a chain of maps, as in `mapA.getOrDefault(key, mapB.getOrDefault(key,
     *   ...))`
     *
     * So it makes sense for the parameter (and thus the return type) to be @CheckForNull.
     *
     * Two other points:
     *
     * 1. We'll want to use something like @PolyNull once we can make that work for the various
     * platforms we target.
     *

const (
	xMinIOHealing = ReservedMetadataPrefix + "healing"
	xMinIODataMov = ReservedMetadataPrefix + "data-mov"
)

// SetHealing marks object (version) as being healed.
// Note: this is to be used only from healObject
func (fi *FileInfo) SetHealing() {
	if fi.Metadata == nil {
		fi.Metadata = make(map[string]string)
	}
	fi.Metadata[xMinIOHealing] = "true"
}

import java.util.Iterator;
import java.util.Queue;
import java.util.concurrent.ConcurrentLinkedQueue;

/**
 * Handler for dispatching events to subscribers, providing different event ordering guarantees that
 * make sense for different situations.
 *
 * <p><b>Note:</b> The dispatcher is orthogonal to the subscriber's {@code Executor}. The dispatcher

 * conformance of concrete {@link Map} subclasses to that contract.
 *
 * @param <K> the type of keys used by the maps under test
 * @param <V> the type of mapped values used the maps under test
 * @author George van den Driessche
 */
// TODO: Descriptive assertion messages, with hints as to probable fixes.

    HashMapImpl {
      @Override
      public <K extends Comparable<K>, V> Map<K, V> create(Map<K, V> map) {
        return Maps.newHashMap(map);
      }
    },
    LinkedHashMapImpl {
      @Override
      public <K extends Comparable<K>, V> Map<K, V> create(Map<K, V> map) {
        return Maps.newLinkedHashMap(map);
      }
    },
    ConcurrentHashMapImpl {
      @Override

<a href="/pkg/sync/#Map">lock-free maps</a>,
<a href="/pkg/sync/#Pool">allocation pools</a>,
and
<a href="/pkg/sync/#WaitGroup">wait groups</a>.
The documentation for each of these specifies the guarantees it
makes concerning synchronization.
</p>

<p>
Other packages that provide synchronization abstractions
should document the guarantees they make too.
</p>

)

func TestUDSLog(t *testing.T) {
	// Start UDS log server
	udsSockDir := t.TempDir()
	udsSock := filepath.Join(udsSockDir, "cni.sock")
	logger := NewUDSLogger(istiolog.DebugLevel)
	stop := make(chan struct{})
	defer close(stop)
	assert.NoError(t, logger.StartUDSLogServer(udsSock, stop))

	// Configure log to tee to UDS server
	stdout := os.Stdout
	r, w, _ := os.Pipe()
	os.Stdout = w