Django deux ForeignKeys à la même erreur d'administration modèle

class UserProfileInline(admin.StackedInline):
    model = Profile
    fk_name = "user"

class SupervisorProfileInline(admin.StackedInline):
    model = Profile
    fk_name = "supervisor"

class NewUserAdmin(NamedUserAdmin):
    inlines = [UserProfileInline, SupervisorProfileInline]

# Django documentation on dealing with this: https://docs.djangoproject.com/en/1.9/ref/contrib/admin/#working-with-a-model-with-two-or-more-foreign-keys-to-the-same-parent-model
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