* and output.
   */
  public void testNewParameterizedTypeImmutability() {
    Type[] typesIn = {String.class, Integer.class};
    ParameterizedType parameterizedType = Types.newParameterizedType(Map.class, typesIn);
    typesIn[0] = null;
    typesIn[1] = null;

    Type[] typesOut = parameterizedType.getActualTypeArguments();
    typesOut[0] = null;
    typesOut[1] = null;

   * and output.
   */
  public void testNewParameterizedTypeImmutability() {
    Type[] typesIn = {String.class, Integer.class};
    ParameterizedType parameterizedType = Types.newParameterizedType(Map.class, typesIn);
    typesIn[0] = null;
    typesIn[1] = null;

    Type[] typesOut = parameterizedType.getActualTypeArguments();
    typesOut[0] = null;
    typesOut[1] = null;

Diese Typen mit inneren Typen werden „**generische**“ Typen genannt. Es ist möglich, sie mit ihren inneren Typen zu deklarieren.

Um diese Typen und die inneren Typen zu deklarieren, können Sie Pythons Standardmodul `typing` verwenden. Es existiert speziell für die Unterstützung dieser Typhinweise.

#### Neuere Python-Versionen

Deze types die interne types hebben worden “**generieke**” types genoemd. Het is mogelijk om ze te declareren, zelfs met hun interne types.

Om deze types en de interne types te declareren, kun je de standaard Python module `typing` gebruiken. Deze module is speciaal gemaakt om deze type hints te ondersteunen.

#### Nieuwere versies van Python

* Sie können alle gültigen Pydantic-Datentypen hier überprüfen: <a href="https://docs.pydantic.dev/latest/usage/types/types/" class="external-link" target="_blank">Pydantic data types</a>.

## Beispiel

Hier ist ein Beispiel für eine *Pfadoperation* mit Parametern, die einige der oben genannten Typen verwenden.

//// tab | Python 3.10+

```Python hl_lines="1  3  12-16"

import types
from enum import Enum
from typing import Any, Callable, Dict, Set, Type, TypeVar, Union

from pydantic import BaseModel

DecoratedCallable = TypeVar("DecoratedCallable", bound=Callable[..., Any])
UnionType = getattr(types, "UnionType", Union)
ModelNameMap = Dict[Union[Type[BaseModel], Type[Enum]], str]

// along with this program.  If not, see <http://www.gnu.org/licenses/>.

package types

// TargetType indicates type of the target e.g. console, http, kafka
type TargetType uint8

//go:generate stringer -type=TargetType -trimprefix=Target $GOFILE

// Constants for target types
const (
	_ TargetType = iota
	TargetConsole
	TargetHTTP
	TargetKafka
)

  }

  private static Type[] toArray(Collection<Type> types) {
    return types.toArray(new Type[0]);
  }

  private static Iterable<Type> filterUpperBounds(Iterable<Type> bounds) {
    return Iterables.filter(bounds, Predicates.not(Predicates.<Type>equalTo(Object.class)));
  }

  private static void disallowPrimitiveType(Type[] types, String usedAs) {
    for (Type type : types) {
      if (type instanceof Class) {

En el mismo punto intentas iniciar el auto-completado con `Ctrl+Space` y ves:

<img src="https://fastapi.tiangolo.com/img/python-types/image02.png">

Con esto puedes moverte hacia abajo viendo las opciones hasta que encuentras una que te suene:

<img src="https://fastapi.tiangolo.com/img/python-types/image03.png">

## Más motivación

Mira esta función que ya tiene type hints:

```Python hl_lines="1"

### Generic types with type parameters

There are some data structures that can contain other values, like `dict`, `list`, `set` and `tuple`. And the internal values can have their own type too.

These types that have internal types are called "**generic**" types. And it's possible to declare them, even with their internal types.