text: from django.db import migrations
  
  from ..classes import DuplicateBackend
  
  
  def operation_initialize_stored_backend_model(apps, schema_editor):
      StoredDuplicateBackend = apps.get_model(
          app_label='duplicates', model_name='StoredDuplicateBackend'
      )
  
      for backend_path, backend_class in DuplicateBackend.get_all():
          stored_backend, created = StoredDuplicateBackend.objects.using(
              alias=schema_editor.connection.alias
          ).get_or_create(
              backend_path=backend_path
          )
  
  
  def operation_initialize_stored_backend_model_reverse(apps, schema_editor):
      StoredDuplicateBackend = apps.get_model(
          app_label='duplicates', model_name='StoredDuplicateBackend'
      )
  
      for stored_backend in StoredDuplicateBackend.objects.using(
          alias=schema_editor.connection.alias
      ).all():
          stored_backend.delete()
  
  
  class Migration(migrations.Migration):
      dependencies = [
          ('duplicates', '0004_storedduplicatebackend'),
      ]
  
      operations = [
          migrations.RunPython(
              code=operation_initialize_stored_backend_model,
              reverse_code=migrations.RunPython.noop
          ),
      ]
  