[Django]-How do I mock a custom field that is deleted so that south migrations run?

South does not hold a reference of deleted field in afterwards migrations. If you deleted the customized field and generated migration successfully, ImportError probably caused by that those customized fields are still referenced by some undone migrations before the deletion migration. So

1. update the code base to the version right before you do the packaging-removing and deletion migration
2. migrate
3. update code base to the deletion migration and migrate

Such simple custom fields are very easy with South 0.7+ if add_introspection_rules [1] have been defined for them. (in the same module after custom field class), when migration was created. Then South does not “freeze” these fields and they can be easily removed. Then if the previous answer from okm does not help you, recreate the old migrations correctry.