///

Now run the live server for the docs in Spanish:

<div class="termy">

```console
// Use the command "live" and pass the language code as a CLI argument
$ python ./scripts/docs.py live es

<span style="color: green;">[INFO]</span> Serving on http://127.0.0.1:8008
<span style="color: green;">[INFO]</span> Start watching changes

        final VaMessenger<FessMessages> messageCode = messages -> messages.addErrorsInvalidQueryUnknown(UserMessages.GLOBAL_PROPERTY_KEY);
        final Exception cause = new IllegalArgumentException("Invalid query argument");

        // Execute
        final InvalidQueryException exception = new InvalidQueryException(messageCode, message, cause);

        // Verify stack trace is captured

///

The only new thing is the `callbacks=invoices_callback_router.routes` as an argument to the *path operation decorator*. We'll see what that is next.

## Documenting the callback { #documenting-the-callback }

The actual callback code will depend heavily on your own API app.

    return (graph instanceof ImmutableValueGraph)
        ? (ImmutableValueGraph<N, V>) graph
        : new ImmutableValueGraph<N, V>(graph);
  }

  /**
   * Simply returns its argument.
   *
   * @deprecated no need to use this
   */
  @InlineMe(
      replacement = "checkNotNull(graph)",
      staticImports = "com.google.common.base.Preconditions.checkNotNull")
  @Deprecated

	for _, collectorPath := range h.metricsData.collectorPaths {
		if collectorPath.isDescendantOf(path) {
			gatherer := h.metricsData.mgGatherers[collectorPath]

			// For Bucket metrics we need to set the buckets argument inside the
			// metric group, so that it will affect collection. If no buckets
			// are provided, we will not return bucket metrics.
			if bmg, ok := h.metricsData.bucketMGMap[collectorPath]; ok {

}

const minReadBufferSize = 16
const maxConsecutiveEmptyReads = 100

// NewReaderSize returns a new [Reader] whose buffer has at least the specified
// size. If the argument io.Reader is already a [Reader] with large enough
// size, it returns the underlying [Reader].
func NewReaderSize(rd io.Reader, size int) *Reader {
	// Is it already a Reader?
	b, ok := rd.(*Reader)

///

Das einzig Neue ist `callbacks=invoices_callback_router.routes` als Argument für den *Pfadoperation-Dekorator*. Wir werden als Nächstes sehen, was das ist.

## Dokumentation des Callbacks

Der tatsächliche Callback-Code hängt stark von Ihrer eigenen API-Anwendung ab.

For example you could have a file `main.py` with:

```Python hl_lines="3"
import os

name = os.getenv("MY_NAME", "World")
print(f"Hello {name} from Python")
```

/// tip

The second argument to <a href="https://docs.python.org/3.8/library/os.html#os.getenv" class="external-link" target="_blank">`os.getenv()`</a> is the default value to return.

Je kunt bijvoorbeeld een bestand `main.py` hebben met:

```Python hl_lines="3"
import os

name = os.getenv("MY_NAME", "World")
print(f"Hello {name} from Python")
```

/// tip

Het tweede argument van <a href="https://docs.python.org/3.8/library/os.html#os.getenv" class="external-link" target="_blank">`os.getenv()`</a> is de standaardwaarde die wordt geretourneerd.

	if ns1 != ns2 {
		return fmt.Errorf("Expected number of endpoints %d, seen %d", ns1, ns2)
	}

	for i, cmdLine := range s1.CmdLines {
		if cmdLine != s2.CmdLines[i] {
			return fmt.Errorf("Expected command line argument %s, seen %s", cmdLine,
				s2.CmdLines[i])
		}
	}

	if reflect.DeepEqual(s1.MinioEnv, s2.MinioEnv) {
		return nil
	}

	// Report differences in environment variables.
	var missing []string