re2o/machines/migrations/0083_remove_duplicate_rights.py

# -*- coding: utf-8 -*-
from __future__ import unicode_literals

from django.db import migrations

def remove_permission_alias(apps, schema_editor):
    Permission = apps.get_model('auth', 'Permission')
    for codename in ['add_alias', 'change_alias', 'delete_alias']:
        # Retrieve the wrong permission
        try:
            to_remove = Permission.objects.get(
                codename=codename,
                content_type__model='domain'
            )
        except Permission.DoesNotExist:
            # The permission is missing so no problem
            pass
        else:
            to_remove.delete()


def remove_permission_text(apps, schema_editor):
    Permission = apps.get_model('auth', 'Permission')
    for codename in ['add_text', 'change_text', 'delete_text']:
        # Retrieve the wrong permission
        try:
            to_remove = Permission.objects.get(
                codename=codename,
                content_type__model='txt'
            )
        except Permission.DoesNotExist:
            # The permission is missing so no problem
            pass
        else:
            to_remove.delete()


class Migration(migrations.Migration):

    dependencies = [
        ('machines', '0082_auto_20180525_2209'),
    ]

    operations = [
        migrations.RunPython(remove_permission_text),
        migrations.RunPython(remove_permission_alias),
    ]