So, what we will do next is add the code to document how that *external API* should look like to receive the callback from *your API*.

That documentation will show up in the Swagger UI at `/docs` in your API, and it will let external developers know how to build the *external API*.

This example doesn't implement the callback itself (that could be just a line of code), only the documentation part.

/// tip

import junit.framework.Test;
import junit.framework.TestSuite;
import org.jspecify.annotations.NullMarked;

/**
 * Unit test for {@link ImmutableSet}.
 *
 * @author Kevin Bourrillion
 * @author Jared Levy
 * @author Nick Kralevich
 */
@GwtCompatible
@NullMarked
public class ImmutableSetTest extends AbstractImmutableSetTest {

  @J2ktIncompatible
  @GwtIncompatible // suite

[tools](https://www.tensorflow.org/resources/tools),
[libraries](https://www.tensorflow.org/resources/libraries-extensions), and
[community](https://www.tensorflow.org/community) resources that lets
researchers push the state-of-the-art in ML and developers easily build and
deploy ML-powered applications.

TensorFlow was originally developed by researchers and engineers working within

     * in any IO with the server. Unlink <code>InputStream</code> value less than
     * the one provided will not be returned if it exceeds the end of the file
     * (if this is a problem let us know).
     */
    @Override
    public long skip(final long n) throws IOException {
        if (n > 0) {
            fp += n;
            return n;
        }
        return 0;
    }

          // Request body headers are only present when installed as a network interceptor. When not
          // already present, force them to be included (if available) so their values are known.
          requestBody.contentType()?.let {
            if (headers["Content-Type"] == null) {
              logger.log("Content-Type: $it")
            }
          }
          if (requestBody.contentLength() != -1L) {

import junit.framework.TestSuite;
import org.jspecify.annotations.NullMarked;
import org.jspecify.annotations.Nullable;

/**
 * Tests for {@link Collections2}.
 *
 * @author Chris Povirk
 * @author Jared Levy
 */
@GwtCompatible
@NullMarked
public class Collections2Test extends TestCase {
  @J2ktIncompatible
  @GwtIncompatible // suite
  @AndroidIncompatible // test-suite builders
  public static Test suite() {

import junit.framework.TestSuite;
import org.jspecify.annotations.NullMarked;
import org.jspecify.annotations.Nullable;

/**
 * Tests for {@link Collections2}.
 *
 * @author Chris Povirk
 * @author Jared Levy
 */
@GwtCompatible
@NullMarked
public class Collections2Test extends TestCase {
  @J2ktIncompatible
  @GwtIncompatible // suite
  @AndroidIncompatible // test-suite builders
  public static Test suite() {

 * </ul>
 *
 * <p>See the Guava User Guide article on <a href=
 * "https://github.com/google/guava/wiki/NewCollectionTypesExplained#table">{@code Table}</a>.
 *
 * @author Jared Levy
 * @param <R> the type of the table row keys
 * @param <C> the type of the table column keys
 * @param <V> the type of the mapped values
 * @since 7.0
 */

 * </ul>
 *
 * <p>See the Guava User Guide article on <a href=
 * "https://github.com/google/guava/wiki/NewCollectionTypesExplained#table">{@code Table}</a>.
 *
 * @author Jared Levy
 * @param <R> the type of the table row keys
 * @param <C> the type of the table column keys
 * @param <V> the type of the mapped values
 * @since 7.0
 */

		if m[err.Error()] > 2 {
			peersLogAlwaysIf(ctx, fmt.Errorf("Following error has been printed %d times.. %w", m[err.Error()], err))
			// Reduce the count to introduce further delay in printing
			// but let it again print after the 2th attempt
			m[err.Error()]--
			m[err.Error()]--
		}
		m[err.Error()]++
	}
}()

// Cleans up tmp directory of the local disk.
func bgFormatErasureCleanupTmp(diskPath string) {