{* ../../docs_src/additional_status_codes/tutorial001_an_py310.py hl[4,25] *}

/// warning

When you return a `Response` directly, like in the example above, it will be returned directly.

It won't be serialized with a model, etc.

Make sure it has the data you want it to have, and that the values are valid JSON (if you are using `JSONResponse`).

///

/// note | "Technical Details"

          data.mappings.escapeDataString(),
        )
        .build(),
    )
    .build()
}

/**
 * KotlinPoet doesn't really know what to do with a string containing NUL, BEL, DEL, etc. We also
 * don't want to perform `trimMargin()` at runtime.
 */
fun String.escapeDataString(): String {
  return buildString {
    for (codePoint in ******@****.***ints()) {
      when (codePoint) {

Flags:

	-D name[=value]
		Predefine symbol name with an optional simple value.
		Can be repeated to define multiple symbols.
	-I dir1 -I dir2
		Search for #include files in dir1, dir2, etc,
		after consulting $GOROOT/pkg/$GOOS_$GOARCH.
	-S
		Print assembly and machine code.
	-V
		Print assembler version and exit.
	-debug
		Dump instructions as they are parsed.
	-dynlink

* Give you the received data in the parameter `item`.
    * As you declared it in the function to be of type `Item`, you will also have all the editor support (completion, etc) for all of the attributes and their types.

* Passer la donnée reçue dans le paramètre `item`.
    * Ce paramètre ayant été déclaré dans la fonction comme étant de type `Item`, vous aurez aussi tout le support offert par l'éditeur (auto-complétion, etc.) pour tous les attributs de ce paramètre et les types de ces attributs.

That defines the metadata about the main response of a *path operation*.

You can also declare additional responses with their models, status codes, etc.

There's a whole chapter here in the documentation about it, you can read it at [Additional Responses in OpenAPI](additional-responses.md){.internal-link target=_blank}.

## OpenAPI Extra

```

</div>

That would work for most of the cases. 😎

You could use that command for example to start your **FastAPI** app in a container, in a server, etc.

## ASGI Servers

Let's go a little deeper into the details.

            e -> e instanceof InvocationTargetException,
            StackOverflowError.class,
            e -> e instanceof StackOverflowError);
      }
    };

    // used under GWT, etc., since the override of this method does not exist there
    ImmutableMap<Class<? extends Throwable>, Predicate<Throwable>> exceptions() {
      return ImmutableMap.of();
    }
  }

            e -> e instanceof InvocationTargetException,
            StackOverflowError.class,
            e -> e instanceof StackOverflowError);
      }
    };

    // used under GWT, etc., since the override of this method does not exist there
    ImmutableMap<Class<? extends Throwable>, Predicate<Throwable>> exceptions() {
      return ImmutableMap.of();
    }
  }

            e -> e instanceof InvocationTargetException,
            StackOverflowError.class,
            e -> e instanceof StackOverflowError);
      }
    };

    // used under GWT, etc., since the override of this method does not exist there
    ImmutableMap<Class<? extends Throwable>, Predicate<Throwable>> exceptions() {
      return ImmutableMap.of();
    }
  }