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# Generated by Django 2.2.7 on 2019-11-19 21:25
from django.db import migrations
from main_app.logic.pure.migrations import is_clean_item
def _set_clean_flag(apps, schema_editor):
"""
Performs the data migration.
We can't import the ``SomeItem`` model directly as it may be a newer
version than this migration expects. We use the historical version.
We are using ``.all()`` because
we don't have a lot of ``SomeItem`` instances.
In real-life you should not do that.
"""
SomeItem = apps.get_model('main_app', 'SomeItem')
for instance in SomeItem.objects.all():
instance.is_clean = is_clean_item(instance)
instance.save(update_fields=['is_clean'])
def _remove_clean_flags(apps, schema_editor):
"""
This is just a noop example of a rollback function.
It is not used in our simple case,
but it should be implemented for more complex scenarios.
"""
class Migration(migrations.Migration):
"""Performs the logical data migration for ``SomeItem``."""
dependencies = [
('main_app', '0002_someitem_is_clean'),
]
operations = [
migrations.RunPython(_set_clean_flag, _remove_clean_flags),
]
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