In a project I have inherited I have a few polymorphic models based on a common model. Something like:

from django.db import models
from polymorphic.models import PolymorphicManager, PolymorphicModel

class Product(PolymorphicModel):
    name=models.CharField(max_length=127)
    objects=PolymorphicManager


class Book(Product):
    pass


class Drink(Product):
    pass

Personally, I would not use polymorphism, but it’s a bit too late for that and way out of scope. I am tasked with adding translations for the name on the base model using parler, however, the documentation for parler only covers translating fields on the child models.

Nevertheless, I modified the models as such:

from django.db import models
from parler.models import TranslatableModel, TranslatedFields
from parler.managers import TranslatableManager, TranslatableQuerySet
from polymorphic.models import PolymorphicManager, PolymorphicModel
from polymorphic.query import PolymorphicQuerySet

class ProductQuerySet(PolymorphicQuerySet, TranslatableQuerySet):
    pass


class ProductManager(PolymorphicManager, TranslatableManager):
    queryset_class = MarkerQuerySet


class Product(PolymorphicModel):
    translations = TranslatedFields(
        name=models.CharField(max_length=127)

    objects=ProductManager


class Book(Product):
    pass


class Drink(Product):
    pass

And it seems to work fine in the django shell:

In [1]: from product.models import Book

In [2]: b0 = Book.objects.first()

In [3]: b0
Out[3]: <Book: A Brief History of Time>

In [4]: b1 = Book()

In [5]: b1.name = 'Hitchhikers Guide to the Galaxy'

In [6]: b1.save()

In [7]: b2 = Book(name='Slaughterhouse V')

In [8]: b2.save()

When I run my endpoint tests, however, I get a somewhat cryptic error:

.venv/lib/python3.12/site-packages/django/db/models/sql/query.py:1577: in _add_q
    child_clause, needed_inner = self.build_filter

.
.
.

>       arg, value = filter_expr
E       ValueError: too many values to unpack (expected 2)

And a different error when I try to see the admin panel for the child models:

Cannot resolve keyword 'name' into field.

I have tried adding a computed properties to the Child models to see if it might fix the admin panel, but it did not. Has anyone any experience with doing something similar?