ValueError when running migration with default value

[sevdog]

When running the makemigrations command if a relativedelta object was provided as default value an error is raised:

File "/opt/venv/lib/python3.9/site-packages/django/db/migrations/serializer.py", line 353, in serializer_factory
    raise ValueError(
ValueError: Cannot serialize: relativedelta(days=+1)
There are some values Django cannot serialize into migration files.
For more, see https://docs.djangoproject.com/en/3.2/topics/migrations/#migration-serializing

It would be useful if this app implements a custom serializer to be used in migrations for relative delta objects.