type Init struct {
	done uint32
	m    sync.Mutex
}

// Do is similar to sync.Once.Do - makes one successful
// call to the function. ie, it invokes the function
// if it is not successful yet.
func (l *Init) Do(f func() error) error {
	if atomic.LoadUint32(&l.done) == 0 {
		return l.do(f)
	}
	return nil
}

func (l *Init) do(f func() error) error {
	l.m.Lock()
	defer l.m.Unlock()

  private val readyAsyncCalls = ArrayDeque<AsyncCall>()

  /** Running asynchronous calls. Includes canceled calls that haven't finished yet. */
  private val runningAsyncCalls = ArrayDeque<AsyncCall>()

  /** Running synchronous calls. Includes canceled calls that haven't finished yet. */
  private val runningSyncCalls = ArrayDeque<RealCall>()

  constructor(executorService: ExecutorService?) : this() {

/**
 * Partial identification of an {@link Artifact} in a Maven repository.
 * Each {@code ArtifactCoordinates} instance is basically a pointer to a file in the Maven repository,
 * except that the exact version may not be known yet.
 *
 * @since 4.0.0
 */
@Experimental
@Immutable
public interface ArtifactCoordinates {
    /**
     * {@return the group identifier of the artifact}
     */
    @Nonnull
    String getGroupId();

    assertFalse(fakePool.hasNext());
    e.execute(intCounter);
    // A task should have been scheduled
    assertTrue(fakePool.hasNext());
    e.execute(intCounter);
    // Our executor hasn't run any tasks yet.
    assertEquals(0, totalCalls.get());
    fakePool.runAll();
    assertEquals(2, totalCalls.get());
    // Queue is empty so no runner should be scheduled.
    assertFalse(fakePool.hasNext());

     *
     * @param project The project to get the build summary for, must not be {@code null}.
     * @return The build summary for the project or {@code null} if the project has not been built (yet).
     */
    BuildSummary getBuildSummary(MavenProject project);

    /**
     * Add the specified build summary.
     *
     * @param summary The build summary to add, must not be {@code null}.
     */

///

Then you could call that Python program:

//// tab | Linux, macOS, Windows Bash

<div class="termy">

```console
// Here we don't set the env var yet
$ python main.py

// As we didn't set the env var, we get the default value

Hello World from Python

// But if we create an environment variable first
$ export MY_NAME="Wade Wilson"

  /**
   * Load cookies from the jar for an HTTP request to [url]. This method returns a possibly
   * empty list of cookies for the network request.
   *
   * Simple implementations will return the accepted cookies that have not yet expired and that
   * [match][Cookie.matches] [url].
   */
  fun loadForRequest(url: HttpUrl): List<Cookie>

  companion object {
    /** A cookie jar that never accepts any cookies. */
    @JvmField

	if err := runPlugin(); err != nil {
		os.Exit(1)
	}
}

func runPlugin() error {
	// Setup initial logging now. We will override it with proper logging over UDS later, but at this point we don't have the config
	// read yet and do not want to be completely blind to logs.
	if err := log.Configure(plugin.GetLoggingOptions(nil)); err != nil {
		return err
	}
	defer func() {
		// Log sync will send logs to install-cni container via UDS.

func bucketUsageMetricsPrometheus(ch chan<- prometheus.Metric) {
	objLayer := newObjectLayerFn()
	// Service not initialized yet
	if objLayer == nil {
		return
	}

	dataUsageInfo, err := loadDataUsageFromBackend(GlobalContext, objLayer)
	if err != nil {
		return
	}
	// data usage has not captured any data yet.
	if dataUsageInfo.LastUpdate.IsZero() {
		return
	}

			sr.fillReady <- int64(n)
		}
	}()

	sr.fillReq <- struct{}{} // initial fill

	return sr
}

// remaining returns the number of unread bytes
// if EOF for the underlying reader has not yet been found,
// maximum possible integer value will be returned
func (s *scanner) remaining() int64 {
	if atomic.LoadInt64(&s.end) == maxInt {
		return maxInt
	}
	return atomic.LoadInt64(&s.end) - s.pos
}