Django Rest Framework自定义权限不起作用

Question

我已经为staff-user实现了django restframework自定义权限类。但就我而言，permission_class无法正常工作。

如果能找出我犯错的地方，那就太好了。

permissions.py：

from rest_framework import permissions

class IsStaff(permissions.BasePermission):

    def has_object_permission(self, request, obj):
        return obj.owner == request.user.is_stff()

views.py：

from .permissions import (IsStaff)

class CuboidListApiView(generics.ListAPIView):
    model = Cuboid
    queryset = Cuboid.objects.all()
    serializer_class = CuboidSerializer
    permission_classes = [IsStaff]