/// check

Also notice that **FastAPI** is smart enough to notice that the path parameter `item_id` is a path parameter and `q` is not, so, it's a query parameter.

///

## Query parameter type conversion

You can also declare `bool` types, and they will be converted:

//// tab | Python 3.10+

```Python hl_lines="7"
{!> ../../docs_src/query_params/tutorial003_py310.py!}
```

////

}
```

/// note

Notice that even though the `item` was declared the same way as before, it is now expected to be inside of the body with a key `item`.

///

**FastAPI** will do the automatic conversion from the request, so that the parameter `item` receives its specific content and the same for `user`.

It will perform the validation of the compound data, and will document it like that for the OpenAPI schema and automatic docs.

* <abbr title="en inglés: serialization, parsing, marshalling">Conversión</abbr> de datos de input: viniendo de la red a datos y tipos de Python. Leyendo desde:
    * JSON.
    * Path parameters.
    * Query parameters.
    * Cookies.
    * Headers.
    * Formularios.
    * Archivos.

   * @throws IllegalArgumentException if the number of actual and formal parameters differ; if an
   *     unwrapping conversion for primitive arguments fails; or if, after possible unwrapping, a
   *     parameter value cannot be converted to the corresponding formal parameter type by a method
   *     invocation conversion.
   * @throws InvocationTargetException if the underlying method or constructor throws an exception.
   */

      /*
       * 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

    # /- - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
    # o dbfluteSystemFinalTimeZone: (NotRequired - Default null)
    #  The ID of time-zone for DBFlute system.
    #  basically for e.g. DisplaySql, Date conversion, LocalDate mapping and so on...
    #
    #; dbfluteSystemFinalTimeZone = GMT
    # - - - - - - - - - -/
}

We could do better.

We can declare a `UserBase` model that serves as a base for our other models. And then we can make subclasses of that model that inherit its attributes (type declarations, validation, etc).

All the data conversion, validation, documentation, etc. will still work as normally.

That way, we can declare just the differences between the models (with plaintext `password`, with `hashed_password` and without password):

func isASCII(s string) bool {
	for _, c := range s {
		if c >= 0x80 || c == 0x00 {
			return false
		}
	}
	return true
}

// toASCII converts the input to an ASCII C-style string.
// This is a best effort conversion, so invalid characters are dropped.
func toASCII(s string) string {
	if isASCII(s) {
		return s
	}
	b := make([]byte, 0, len(s))
	for _, c := range s {
		if c < 0x80 && c != 0x00 {
			b = append(b, byte(c))

  // 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) {

/// 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.