Sie geben den ersten Parameter der Funktion ein, `first_name`, dann einen Punkt (`.`) und drücken `Strg+Leertaste`, um die Vervollständigung auszulösen.

Aber leider erhalten Sie nichts Nützliches:

<img src="/img/python-types/image01.png">

### Typen hinzufügen { #add-types }

Lassen Sie uns eine einzelne Zeile aus der vorherigen Version ändern.

/// info | Info

Das obige Beispiel ist tatsächlich eine Ausnahme, weil sich das `io.BytesIO`-Objekt bereits im Speicher befindet, daher blockiert sein Lesen nichts.

Aber in vielen Fällen würde das Lesen einer Datei oder eines dateiähnlichen Objekts blockieren.

///

The **Advanced User Guide** builds on this one, uses the same concepts, and teaches you some extra features.

But you should first read the **Tutorial - User Guide** (what you are reading right now).

		// specified in the Forwarded header. The first element will always be
		// the 'for=', which we ignore, subsequently we proceed to look for
		// 'proto=' which should precede right after `for=` if not
		// we simply ignore the values and return empty. This is in line
		// with the approach we took for returning first ip from multiple
		// params.

Whenever a participant has made a mistake, we expect them to take responsibility for it. If someone
has been harmed or offended, it is our responsibility to listen carefully and respectfully, and do
our best to right the wrong.

Although this list cannot be exhaustive, we explicitly honor diversity in age, culture, ethnicity,
gender identity or expression, language, national origin, political beliefs, profession, race,

                try {
                  startUp();
                  notifyStarted();
                  // If stopAsync() is called while starting we may be in the STOPPING state in
                  // which case we should skip right down to shutdown.
                  if (isRunning()) {
                    try {
                      AbstractExecutionThreadService.this.run();
                    } catch (Throwable t) {

Now, there are some cases where you might want to have the **same schema for input and output**.

Probably the main use case for this is if you already have some autogenerated client code/SDKs and you don't want to update all the autogenerated client code/SDKs yet, you probably will want to do it at some point, but maybe not right now.

			case <-doneCh:
				return nil
			}
		}
	}
	return sys.pubsub.Subscribe(madmin.LogMaskAll, subCh, doneCh, filter)
}

// Init if HTTPConsoleLoggerSys is valid, always returns nil right now
func (sys *HTTPConsoleLoggerSys) Init(_ context.Context) error {
	return nil
}

// Endpoint - dummy function for interface compatibility
func (sys *HTTPConsoleLoggerSys) Endpoint() string {

---

If you just don't know, use normal `def`.

---

**Note**: You can mix `def` and `async def` in your *path operation functions* as much as you need and define each one using the best option for you. FastAPI will do the right thing with them.

Anyway, in any of the cases above, FastAPI will still work asynchronously and be extremely fast.

But by following the steps above, it will be able to do some performance optimizations.

   *     invocation conversion.
   * @throws InvocationTargetException if the underlying method or constructor throws an exception.
   */
  // All subclasses are owned by us and we'll make sure to get the R type right, including nullness.
  @SuppressWarnings({"unchecked", "nullness"})
  @CanIgnoreReturnValue
  public final @Nullable R invoke(@Nullable T receiver, @Nullable Object... args)