          """
          if self.context_object_name:
              return self.context_object_name
          elif isinstance(obj, models.Model):
              if obj._deferred:
                  obj = obj._meta.proxy_for_model
              return obj._meta.model_name
          else:
              return None
  
      def get_context_data(self, **kwargs):
 
</s> remove         model = obj._meta.proxy_for_model if obj._deferred else obj.__class__
        data = OrderedDict([('model', force_text(model._meta))])
 </s> add         data = OrderedDict([('model', force_text(obj._meta))]) </s> remove         if not self._deferred:
            class_id = self._meta.app_label, self._meta.object_name
            return model_unpickle, (class_id, [], simple_class_factory), data
        defers = []
        for field in self._meta.fields:
            if isinstance(self.__class__.__dict__.get(field.attname),
                          DeferredAttribute):
                defers.append(field.attname)
        model = self._meta.proxy_for_model
        class_id = model._meta.app_label, model._meta.object_name
        return (model_unpickle, (class_id, defers, deferred_class_factory), data)
 </s> add         class_id = self._meta.app_label, self._meta.object_name
        return model_unpickle, (class_id,), data </s> remove             if isinstance(self.__class__.__dict__.get(f.attname), DeferredAttribute)
 </s> add             if f.attname not in self.__dict__ </s> remove         geo_value = instance.__dict__[self._field.attname]
 </s> add         try:
            geo_value = instance.__dict__[self._field.attname]
        except KeyError:
            geo_value = super(SpatialProxy, self).__get__(instance, cls) </s> remove     def get_deferred_cls(self, klass_info, init_list):
        model_cls = klass_info['model']
        if len(init_list) != len(model_cls._meta.concrete_fields):
            init_set = set(init_list)
            skip = [
                f.attname for f in model_cls._meta.concrete_fields
                if f.attname not in init_set
            ]
            model_cls = deferred_class_factory(model_cls, skip)
        return model_cls

 </s> add 
          """
          if self.context_object_name:
              return self.context_object_name
          elif isinstance(obj, models.Model):


              return obj._meta.model_name
          else:
              return None
  
      def get_context_data(self, **kwargs):
keep keep keep keep replace replace keep keep keep keep keep
 Fixed #26207 -- Replaced dynamic classes with non-data descriptors for deferred instance loading. 
django/views/generic/detail.py