'Return all shelves a user can administer. Anonymous users will always
receive an empty list.'

def mine(self, request, *args, **kwargs):

    qs = self.queryset
    if request.user.is_anonymous():
        qs = self.queryset.none()
    elif (not self.is_admin(request.user)):
        perms = OperatorPermission.objects.filter(user=request.user)
        if perms:
            query = Q()
            for perm in perms:
                query |= Q(carrier=perm.carrier, region=perm.region)
            qs = self.queryset.filter(query)
        else:
            qs = self.queryset.none()
    self.object_list = self.filter_queryset(qs)
    serializer = self.get_serializer(self.object_list, many=True)
    return Response(serializer.data)
