## Response Adicional con `model`

Puedes pasar a tus *decoradores de path operation* un parámetro `responses`.

Recibe un `dict`: las claves son los códigos de estado para cada response (como `200`), y los valores son otros `dict`s con la información para cada uno de ellos.

@DoNotMock("Use ImmutableRangeMap or TreeRangeMap")
@GwtIncompatible
public interface RangeMap<K extends Comparable, V> {
  /*
   * TODO(cpovirk): These docs sometimes say "map" and sometimes say "range map." Pick one, or at
   * least decide on a policy for when to use which.
   */

  /**
   * Returns the value associated with the specified key, or {@code null} if there is no such value.
   *

        return null // Nothing to do.
      }

      val now = backend.nanoTime()
      var minDelayNanos = Long.MAX_VALUE
      var readyTask: Task? = null
      var multipleReadyTasks = false

      // Decide what to run. This loop's goal wants to:
      //  * Find out what this thread should do (either run a task or sleep)
      //  * Find out if there's enough work to start another thread.

     *
     * @param <P>           the type of problem
     * @param maxCountLimit the maximum number of problems to preserve
     * @param filter        predicate to decide which problems to record
     * @return a new filtered problem collector instance
     */
    @Nonnull
    static <P extends BuilderProblem> ProblemCollector<P> create(int maxCountLimit, Predicate<? super P> filter) {

The dictionary in `openapi_extra` will be deeply merged with the automatically generated OpenAPI schema for the *path operation*.

So, you could add additional data to the automatically generated schema.

For example, you could decide to read and validate the request with your own code, without using the automatic features of FastAPI with Pydantic, but you could still want to define the request in the OpenAPI schema.

You could do that with `openapi_extra`:

{* ../../docs_src/path_params/tutorial003b.py hl[6,11] *}

La primera siempre será utilizada ya que el path coincide primero.

## Valores predefinidos

Si tienes una *path operation* que recibe un *path parameter*, pero quieres que los valores posibles válidos del *path parameter* estén predefinidos, puedes usar un <abbr title="Enumeration">`Enum`</abbr> estándar de Python.

### Crear una clase `Enum`

    val existingRouteSelection = routeSelection
    if (existingRouteSelection != null && existingRouteSelection.hasNext()) {
      return planConnectToRoute(existingRouteSelection.next())
    }

    // Decide which proxy to use, if any. This may block in ProxySelector.select().
    var newRouteSelector = routeSelector
    if (newRouteSelector == null) {
      newRouteSelector =
        RouteSelector(

        return int(sip.Sum64() % uint64(cardinality))
}
```

Input for the key is the object name specified in `PutObject()`, returns a unique index. This index is one of the erasure sets where the object will reside. This function is a consistent hash for a given object name i.e for a given object name the index returned is always the same.

* **function**: es la función debajo del "decorador" (debajo de `@app.get("/")`).

{* ../../docs_src/first_steps/tutorial001.py hl[7] *}

Esta es una función de Python.

Será llamada por **FastAPI** cuando reciba un request en la URL "`/`" usando una operación `GET`.

En este caso, es una función `async`.

---

También podrías definirla como una función normal en lugar de `async def`:

						},
					},
				},
			},
		})
	})

	t.Run("has one with custom polymorphic type and id", func(t *testing.T) {
		type Toy struct {
			ID    int
			Name  string
			RefId int
			Type  string
		}

		type Cat struct {
			ID   int
			Name string
			Toy  Toy `gorm:"polymorphic:Owner;polymorphicType:Type;polymorphicId:RefId"`
		}