/// note

"Notez que, bien que nous ayons déclaré le paramètre `item` de la même manière que précédemment, il est maintenant associé à la clé `item` dans le corps de la requête."`.

///

**FastAPI** effectue la conversion de la requête de façon transparente, de sorte que les objets `item` et `user` se trouvent correctement définis.

Prefer to use the `Annotated` version if possible.

///

```Python
commons: CommonQueryParams ...
```

////

...doesn't have any special meaning for **FastAPI**. FastAPI won't use it for data conversion, validation, etc. (as it is using the `Depends(CommonQueryParams)` for that).

You could actually write just:

//// tab | Python 3.8+

```Python
commons: Annotated[Any, Depends(CommonQueryParams)]
```

/// check

This will give you editor support inside of your function, with error checks, completion, etc.

///

## Data <abbr title="also known as: serialization, parsing, marshalling">conversion</abbr>

If you run this example and open your browser at <a href="http://127.0.0.1:8000/items/3" class="external-link" target="_blank">http://127.0.0.1:8000/items/3</a>, you will see a response of:

```JSON
{"item_id":3}

/// check | Revisa

Esto te dará soporte en el editor dentro de tu función, con chequeo de errores, auto-completado, etc.

///

## <abbr title="también conocido en inglés como: serialization, parsing, marshalling">Conversión</abbr> de datos

Si corres este ejemplo y abres tu navegador en <a href="http://127.0.0.1:8000/items/3" class="external-link" target="_blank">http://127.0.0.1:8000/items/3</a> verás una respuesta de:

```JSON
{"item_id":3}

      /*
       * For most values, the conversion from roundArbitrarily to roundArbitrarilyAsLong is
       * lossless. In that case we can compare x to roundArbitrarily using Long.compare(x,
       * roundArbitrarilyAsLong). The exception is for values where the conversion to double rounds
       * up to give roundArbitrarily equal to 2^63, so the conversion back to long overflows and

        final String text = value.trim();

        final Class<?> rawType = toType.getRawType();
        if (rawType.isAssignableFrom(String.class)) {
            return text; // compatible type => no conversion needed
        }

        // use temporary Key as quick way to auto-box primitive types into their equivalent object types
        final TypeLiteral<?> boxedType =

  // TODO: IdentityHashMap, AbstractMap

  private static Map<String, String> toHashMap(Entry<String, String>[] entries) {
    return populate(new HashMap<String, String>(), entries);
  }

  // TODO: call conversion constructors or factory methods instead of using
  // populate() on an empty map
  private static <T, M extends Map<T, String>> M populate(M map, Entry<T, String>[] entries) {
    for (Entry<T, String> entry : entries) {

* <abbr title="also known as: serialization, parsing, marshalling">Conversion</abbr> of input data: coming from the network to Python data and types. Reading from:
    * JSON.
    * Path parameters.
    * Query parameters.
    * Cookies.
    * Headers.
    * Forms.
    * Files.

* <abbr title="also known as: serialization, parsing, marshalling">Conversion</abbr> of input data: coming from the network to Python data and types. Reading from:
    * JSON.
    * Path parameters.
    * Query parameters.
    * Cookies.
    * Headers.
    * Forms.
    * Files.

   with its <<<DefaultReportConfigurationExpander>>> implementation
   ({{{./xref/org/apache/maven/model/plugin/DefaultReportConfigurationExpander.html}source}})

   ** <(optional)> reports conversion to decoupled site plugin: <<<ReportingConverter>>> ({{{./apidocs/org/apache/maven/model/plugin/ReportingConverter.html}javadoc}}),
   with its <<<DefaultReportingConverter>>> implementation