Es un plug-in para muchos frameworks (y hay un plug-in para Starlette también).

La manera en que funciona es que escribes la definición del esquema usando el formato YAML dentro del docstring de cada función que maneja una ruta.

Y genera esquemas OpenAPI.

Así es como funciona en Flask, Starlette, Responder, etc.

  }

  /**
   * A function from an input to a result.
   *
   * @param <T> the type of the input to the function
   * @param <U> the type of the result of the function
   */
  public interface ClosingFunction<T extends @Nullable Object, U extends @Nullable Object> {

    /**
     * Applies this function to an input, or throws an exception if unable to do so.
     *

        /*
         * We can assume that Kotlin code is performing the null checks that we want, since kotlinc
         * inserts checks automatically for non-private functions (which are the only kind that we
         * check).
         *
         * We *would* just check such functions redundantly, but kotlinc emits its nullness
         * annotations in the form of JetBrains annotations, which have only class retention and

import javax.inject.Inject;
import javax.inject.Named;
import javax.inject.Singleton;

import java.io.ByteArrayOutputStream;
import java.io.PrintStream;
import java.util.List;
import java.util.Map;
import java.util.function.Supplier;

import org.apache.maven.api.Project;
import org.apache.maven.api.Service;
import org.apache.maven.api.services.MavenException;
import org.apache.maven.execution.MavenSession;

		"Total number of bytes received", "type")
)

// loadAPIRequestsHTTPMetrics - reads S3 HTTP metrics.
//
// This is a `MetricsLoaderFn`.
//
// This includes node level S3 HTTP metrics.
//
// This function currently ignores `opts`.
func loadAPIRequestsHTTPMetrics(ctx context.Context, m MetricValues, _ *metricsCache) error {
	// Collect node level S3 HTTP metrics.
	httpStats := globalHTTPStats.toServerHTTPStats(false)

	return true
}

// teardown - cleans up test directories.
func teardown(testResults []result) {
	for _, r := range testResults {
		os.RemoveAll(r.dir)
	}
}

// TestReadDir - test function to run various readDir() tests.
func TestReadDir(t *testing.T) {
	var testResults []result

	// Setup and capture test results for empty directory.
	testResults = append(testResults, setupTestReadDirEmpty(t)...)

}

// client to talk to bootstrap NEndpoints.
type bootstrapRESTClient struct {
	gridConn *grid.Connection
}

// Verify function verifies the server config.
func (client *bootstrapRESTClient) Verify(ctx context.Context, srcCfg *ServerSystemConfig) (err error) {
	if newObjectLayerFn() != nil {
		return nil
	}

```

El parámetro `name` sigue siendo **requerido** (no *opcional*) porque no tiene un valor predeterminado. Aún así, `name` acepta `None` como valor:

```Python
say_hi(name=None)  # Esto funciona, None es válido 🎉
```

La buena noticia es que, una vez que estés en Python 3.10, no tendrás que preocuparte por eso, ya que podrás simplemente usar `|` para definir uniones de tipos:

import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Set;
import java.util.concurrent.atomic.AtomicBoolean;
import java.util.function.Predicate;
import junit.framework.Test;
import junit.framework.TestCase;
import junit.framework.TestSuite;
import org.jspecify.annotations.Nullable;

/**

import java.time.format.DateTimeFormatter;
import java.util.Arrays;
import java.util.List;
import java.util.Locale;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.TimeUnit;
import java.util.function.BiConsumer;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import java.util.stream.Collectors;
import java.util.stream.Stream;

/**