[Python] How to handle existing data when introducing an intermediate model between a base...

Current models:

class Task(PolymorphicModel):
pass

class DownloadTask(Task):
pass


New models: And now i want to do add a new layer called VirtualTask:

class Task(PolymorphicModel):
pass

class VirtualTask(Task):
pass

class DownloadTask(VirtualTask):
pass


Migration it looks like this:

class Migration(migrations.Migration):

dependencies = [
("tasks", "0005_alter_task_last_error"),
]

operations = [
migrations.CreateModel(
name="VirtualTask",
fields=[
(
"task_ptr",
models.OneToOneField(
auto_created=True,
on_delete=django.db.models.deletion.CASCADE,
parent_link=True,
primary_key=True,
serialize=False,
to="tasks.task",
),
),
],
options={
"abstract": False,
"base_manager_name": "objects",
},
bases=("tasks.task",),
),
migrations.RemoveField(
model_name="downloadtask",
name="task_ptr",
),
migrations.AddField(
model_name="downloadtask",
name="virtualptask_ptr",
field=models.OneToOneField(
auto_created=True,
default=1,
on_delete=django.db.models.deletion.CASCADE,
parent_link=True,
primary_key=True,
serialize=False,
to="tasks.virtualtask",
),
preserve_default=False,
),
]


“How should I handle existing data when inserting a new intermediate model (VirtualTask) between a base model (Task) and its subclasses in Django

• should I customize the migration file, and if so, what would be the step-by-step approach?”

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