Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

    This is not a limitation of **FastAPI**, it's part of the HTTP protocol.

## Recap

# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to
# deal in the Software without restriction, including without limitation the
# rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
# sell copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:

    This is not a limitation of **FastAPI**, it's part of the HTTP protocol.

## Optional File Upload

You can make a file optional by using standard type annotations and setting a default value of `None`:

=== "Python 3.10+"

* Concatène les résultats avec un espace entre les deux.

```Python hl_lines="2"
{!../../../docs_src/python_types/tutorial001.py!}
```

### Limitations

C'est un programme très simple.

Mais maintenant imaginez que vous l'écriviez de zéro.

À un certain point vous auriez commencé la définition de la fonction, vous aviez les paramètres prêts.

    Das ist keine Limitation von **FastAPI**, sondern Teil des HTTP-Protokolls.

## Zusammenfassung

    Das ist keine Limitation von **FastAPI**, sondern Teil des HTTP-Protokolls.

## Optionaler Datei-Upload

Sie können eine Datei optional machen, indem Sie Standard-Typannotationen verwenden und den Defaultwert auf `None` setzen:

    This is not a limitation of **FastAPI**, it's part of the HTTP protocol.

## Recap

    Das ist keine Limitation von **FastAPI**, sondern Teil des HTTP-Protokolls.

## Zusammenfassung