`response_model` receives the same type you would declare for a Pydantic model field, so, it can be a Pydantic model, but it can also be, e.g. a `list` of Pydantic models, like `List[Item]`.

FastAPI will use this `response_model` to do all the data documentation, validation, etc. and also to **convert and filter the output data** to its type declaration.

!!! tip

  <modules>
    <module>maven-api-meta</module>
    <module>maven-api-di</module>
    <module>maven-api-xml</module>
    <module>maven-api-model</module>
    <module>maven-api-plugin</module>
    <module>maven-api-settings</module>
    <module>maven-api-toolchain</module>
    <module>maven-api-metadata</module>
    <module>maven-api-core</module>
    <module>maven-api-spi</module>
  </modules>

## Composition by architecture modules

Each [architecture module and platform](platforms.md) can contribute code to any of the elements.
Not every module contributes to every element.

## Deeply nested models

You can define arbitrarily deeply nested models:

=== "Python 3.10+"

    ```Python hl_lines="7  12  18  21  25"
    {!> ../../../docs_src/body_nested_models/tutorial007_py310.py!}
    ```

=== "Python 3.9+"

    ```Python hl_lines="9  14  20  23  27"
    {!> ../../../docs_src/body_nested_models/tutorial007_py39.py!}
    ```

=== "Python 3.8+"

relationships:
</p>

<pre>
x = q*y + r  and  |r| &lt; |y|
</pre>

<p>
with <code>x / y</code> truncated towards zero
(<a href="https://en.wikipedia.org/wiki/Modulo_operation">"truncated division"</a>).
</p>

<pre>
 x     y     x / y     x % y
 5     3       1         2
-5     3      -1        -2
 5    -3      -1         2
-5    -3       1        -2

Moustapha Sall <******@****.***> 1704810933 -0500

relationships:
</p>

<pre>
x = q*y + r  and  |r| &lt; |y|
</pre>

<p>
with <code>x / y</code> truncated towards zero
(<a href="https://en.wikipedia.org/wiki/Modulo_operation">"truncated division"</a>).
</p>

<pre>
 x     y     x / y     x % y
 5     3       1         2
-5     3      -1        -2
 5    -3      -1         2
-5    -3       1        -2

```

Aqui nós estamos simulando a *inicialização* custosa do carregamento do modelo colocando a (falsa) função de modelo no dicionário com modelos de _machine learning_ antes do `yield`. Este código será executado **antes** da aplicação **começar a receber requisições**, durante a *inicialização*.

# OpenAPI-`models`

OpenAPI Pydantic-Modelle, werden zum Generieren und Validieren der generierten OpenAPI verwendet.

Moustapha Sall <******@****.***> 1704810933 -0500