docs: def cauldron_extras(self):
          """ Yield extra tuples containing a field name and a callable that takes
          a row
          """
          for extra in super(Dimension, self).cauldron_extras:
              yield extra
  
          if self.formatters:
              prop = self.id + '_raw'
          else:
              prop = self.id_prop
  
          yield self.id + '_id', lambda row: getattr(row, prop)