[Python] Association de classes

class Application:
    def__init__(self, Description, Importance, Marche, Offre_commerciale,   Vocation, Date_cre, Dat_mod)
        self.Description = Description
        self.Importance = Importance
        self.Marche = Marche
        self.Offre_commerciale = Offre_commerciale
        self.Vocation = Vocation
        self.Date_cre = Date_cre
        self.Date_mod = Date_mod

        #Tes versions
        self.versions = []

     # A toi de valider les paramètres ici
     def addVersion(self, Description, Date_version, Date_mep):
        version = App_version(self, Description, Date_version, Date_mep)
        self.versions.append(version)

class App_version:
    def__init__(self, App, Description, Date_version, Date_mep)
        self.Description = Description
        self.Date_version = Date_version
        self.Date_mep = Date_mep
        #Vérifier le paramètre App...
        self.App = App

class Application:
    def __new__(classe):
        instance = object.__new__(classe)
        instance.versions = []
        default_version = App_version( instance, cquetuveux, cquetuveux, cquetuveux)
        instance.versions.append(default_version)
        return instance