from dataclasses import dataclass
from typing import Callable

@dataclass
class User:
    username: str
    is_authenticated: bool = False

def authentication_required(fonction: Callable):
    def internal_wrapper(user: User):
        if not user.is_authenticated:
            return PermissionError(f"L'utilisateur {user.username} n'est pas authentifié.")
        return fonction(user)
    return internal_wrapper
        
@authentication_required
def operation_sensible(user: User):
    return f"Opération sensible faite par {user.username}."

alice = User("alice@courriel.fr", True)
bob = User("bob@courriel.fr")

print(operation_sensible(alice))
print(operation_sensible(bob))