How to use the robotframework.models.Webcase.objects function in robotframework

def webUI_periodic_task(request):
    username = request.session.get('user','')
    tasks = webtest_task.objects.all()
    cases = Webcase.objects.all()
    singel_tasks = webtest_task.objects.get_queryset().order_by('task_id')
    paginator = Paginator(singel_tasks, 15)  # 生成paginator对象,设置每页显示15条记录
    page = request.GET.get('page', 1)  # 获取当前页为第1页
    currentPage = int(page)  # 把当前页转换成整数
    try:
        singel_tasks = paginator.page(page)  # 获取当前页码数的记录列表
    except PageNotAnInteger:
        singel_tasks = paginator.page(1)  # 如果输入的页数不是整数则显示第1页内容
    except EmptyPage:
        singel_tasks = paginator.page(paginator.num_pages)  # 如果输入的的页数不在系统的页数中，则显示最后一页
    return  render(request, "webcase_periodic_task.html", {"user": username, "singel_tasks": singel_tasks,"cases":cases,"tasks": tasks})