code: def change_view(self, request, object_id, form_url='', extra_context=None):
          
  
          obj = self.get_object(request, unquote(object_id))
  
          if obj is None:
              raise Http404(_('%(name)s object with primary key %(key)r does not exist.') % {
                  'name': force_text(self.opts.verbose_name),
                  'key': escape(object_id),
              })
  
          if not self.has_change_permission(request, obj):
              raise PermissionDenied
  
          content_block = obj.content_block
          version = content_block.obj_version
  
          # Version must not be saved, and must belong to this user
          if version.version_number or version.owner != request.user:
              raise PermissionDenied
  
          return super().change_view(request, object_id, form_url, extra_context)
docs: The 'change' admin view for this model.