## Eine „aufrufbare“ Instanz

In Python gibt es eine Möglichkeit, eine Instanz einer Klasse „aufrufbar“ („callable“) zu machen.

Nicht die Klasse selbst (die bereits aufrufbar ist), sondern eine Instanz dieser Klasse.

Dazu deklarieren wir eine Methode `__call__`:

{* ../../docs_src/dependencies/tutorial011_an_py39.py hl[12] *}

import org.codelibs.core.beans.converter.TimeConverter;
import org.codelibs.core.beans.converter.TimestampConverter;
import org.codelibs.core.convert.DateConversionUtil;
import org.codelibs.core.convert.TimeConversionUtil;
import org.codelibs.core.convert.TimestampConversionUtil;
import org.codelibs.core.exception.ConverterRuntimeException;

/**

        return asJson(new ApiResponse().status(Status.OK).result());
    }

    /**
     * Creates an edit body from a job log entity for API responses.
     *
     * @param entity the job log entity to convert
     * @return edit body containing the entity data
     */
    protected EditBody createEditBody(final JobLog entity) {
        final EditBody body = new EditBody();
        copyBeanToBean(entity, body, copyOp -> {

 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
 * either express or implied. See the License for the specific language
 * governing permissions and limitations under the License.
 */
package org.codelibs.core.convert;

import static java.text.DateFormat.FULL;
import static java.text.DateFormat.LONG;
import static java.text.DateFormat.MEDIUM;
import static java.text.DateFormat.SHORT;
import static java.text.DateFormat.getDateInstance;

Because the editor knows the types of the variables, you don't only get completion, you also get error checks:

<img src="/img/python-types/image04.png">

Now you know that you have to fix it, convert `age` to a string with `str(age)`:

{* ../../docs_src/python_types/tutorial004.py hl[2] *}

## Declaring types { #declaring-types }

You just saw the main place to declare type hints. As function parameters.

You can also use Pydantic models as subtypes of `list`, `set`, etc.:

{* ../../docs_src/body_nested_models/tutorial006_py310.py hl[18] *}

This will expect (convert, validate, document, etc.) a JSON body like:

```JSON hl_lines="11"
{
    "name": "Foo",
    "description": "The pretender",
    "price": 42.0,
    "tax": 3.2,
    "tags": [
        "rock",

Das ist keine Limitation von **FastAPI**, sondern Teil des HTTP-Protokolls.

///

## Zusammenfassung

        return asJson(new ApiResponse().status(Status.OK).result());
    }

    /**
     * Creates an EditBody from a RelatedQuery entity for API responses.
     *
     * @param entity the RelatedQuery entity to convert
     * @return EditBody containing the entity data formatted for editing
     */
    protected EditBody createEditBody(final RelatedQuery entity) {
        final EditBody body = new EditBody();

        while (i < end) {
          keyIndex %= keyLength // Reassign to prevent overflow breaking counter.

          // Byte xor is experimental in Kotlin so we coerce bytes to int, xor them
          // and convert back to byte.
          val bufferInt: Int = buffer[i].toInt()
          val keyInt: Int = key[keyIndex].toInt()
          buffer[i] = (bufferInt xor keyInt).toByte()

          i++
          keyIndex++

9. Diese *Pfadoperation-Funktion* gibt keine Datenklassen zurück (obwohl dies möglich wäre), sondern eine Liste von Dictionarys mit internen Daten.

    FastAPI verwendet den Parameter `response_model` (der Datenklassen enthält), um die Response zu konvertieren.