old_contents: 
  from south.db import db
  from django.db import models
  
  from ella.core.migrations.base.base_0002 import BasePublishableDataMigration
  from ella.core.migrations.base.base_0002 import alter_foreignkey_to_int, migrate_foreignkey
  
  
  class Migration(BasePublishableDataMigration):
      models = dict.copy(BasePublishableDataMigration.models)
      models.update(
          {
              'polls.quiz': {
                  'Meta': {'ordering': "('-active_from',)", '_bases': ['ella.core.models.publishable.Publishable']},
                  'active_from': ('models.DateTimeField', ["_('Active from')"], {}),
                  'active_till': ('models.DateTimeField', ["_('Active till')"], {}),
                  'has_correct_answers': ('models.BooleanField', ["_('Has correct answers')"], {}),
                  'publishable_ptr': ('models.OneToOneField', ["orm['core.Publishable']"], {}),
                  'text': ('models.TextField', ["_('Text')"], {}),
                  'text_announcement': ('models.TextField', ["_('Text with announcement')"], {}),
                  'text_results': ('models.TextField', ["_('Text with results')"], {})
              },
          }
      )
  
      app_label = 'polls'
      model = 'quiz'
      table = '%s_%s' % (app_label, model)
  
      publishable_uncommon_cols = {}
      
      def alter_self_foreignkeys(self, orm):
          # migrate authors as in base
          super(Migration, self).alter_self_foreignkeys(orm)
          alter_foreignkey_to_int('polls_question', 'quiz', null=True)
          alter_foreignkey_to_int('polls_result', 'quiz')
  
      def move_self_foreignkeys(self, orm):
          # migrate authors as in base
          super(Migration, self).move_self_foreignkeys(orm)
          # migrate new quiz IDs to question
          migrate_foreignkey(self.app_label, self.model, 'polls_question', self.model, self.orm, null=True)
          # migrate new quiz IDs to results
          migrate_foreignkey(self.app_label, self.model, 'polls_result', self.model, self.orm)
  
  
new_contents: 
  from south.db import db
  from django.db import models
  
  from ella.core.migrations.base.base_0002 import BasePublishableDataMigration
  from ella.core.migrations.base.base_0002 import alter_foreignkey_to_int, migrate_foreignkey
  
  
  class Migration(BasePublishableDataMigration):
      models = dict.copy(BasePublishableDataMigration.models)
      models.update(
          {
              'polls.quiz': {
                  'Meta': {'ordering': "('-active_from',)", '_bases': ['ella.core.models.publishable.Publishable']},
                  'active_from': ('models.DateTimeField', ["_('Active from')"], {}),
                  'active_till': ('models.DateTimeField', ["_('Active till')"], {}),
                  'has_correct_answers': ('models.BooleanField', ["_('Has correct answers')"], {}),
                  'publishable_ptr': ('models.OneToOneField', ["orm['core.Publishable']"], {}),
                  'text': ('models.TextField', ["_('Text')"], {}),
                  'text_announcement': ('models.TextField', ["_('Text with announcement')"], {}),
                  'text_results': ('models.TextField', ["_('Text with results')"], {})
              },
          }
      )
  
      app_label = 'polls'
      model = 'quiz'
      table = '%s_%s' % (app_label, model)
  
      publishable_uncommon_cols = {
          'description': 'text_announcement'
      }
      
      def alter_self_foreignkeys(self, orm):
          # migrate authors as in base
          super(Migration, self).alter_self_foreignkeys(orm)
          alter_foreignkey_to_int('polls_question', 'quiz', null=True)
          alter_foreignkey_to_int('polls_result', 'quiz')
  
      def move_self_foreignkeys(self, orm):
          # migrate authors as in base
          super(Migration, self).move_self_foreignkeys(orm)
          # migrate new quiz IDs to question
          migrate_foreignkey(self.app_label, self.model, 'polls_question', self.model, self.orm, null=True)
          # migrate new quiz IDs to results
          migrate_foreignkey(self.app_label, self.model, 'polls_result', self.model, self.orm)
  
  
subject: use text_announcement as source for quiz's description