code: def qs_field(
      model_class,
      field,
      filters=None,
      formatter=queryset_formatter,
      manager_name='objects',
  ):
      
      if filters is None:
          filters = {}
  
      def _(view, context, _model, name):
          filters[field] = _model  # e.g. students: user
  
          # e.g. User.objects, User.deleted_objects
          manager = getattr(model_class, manager_name)
          return formatter(manager(**filters))
  
      return _
docs: Show computed fields based on QuerySet's.
  
      This is a workaround since sometimes some filtering is involved to see if a user
      owns and object, is a student, etc.
  
      Example
      -------
      class MyModel(ModelView):
          details_extra_columns = [
              ('courses_owned', 'Courses (Owner of)'),
          ]
          column_formatters_detail = {
              'courses_owner': qs_field(model.Course, 'owner'),
          ]