code: def add_display(cls, attr, title=''):
          
          global klass_count
          klass_count += 1
          fn_name = 'dyn_fn_%d' % klass_count
          cls.list_display.append(fn_name)
  
          if not title:
              title = attr.capitalize()
  
          def _ref(self, obj):
              # use the django mechanism for field value lookup
              _, _, value = lookup_field(attr, obj, cls)
              return value
          _ref.short_description = title
          _ref.allow_tags = True
          _ref.admin_order_field = attr
  
          setattr(cls, fn_name, _ref)
docs: Adds a ``list_display`` property without any extra wrappers,
          similar to :func:`add_displays`, but can also change the title.
  
          :param attr:
              Name of the attribute to add to the display
  
          :param title:
              Title for the column of the django admin table.  If not given it
              defaults to a capitalized version of ``attr``