要求实现堆排序。请填写横线处代码，完善筛选法heapSift函数和堆排序heapSort函数，并把整段代码复制黏贴到代码提交区。

def heapSift(nums, start, end):
    root = start
    while True:
        child = 2 * root + 1
        if child > end:
            break
        if child + 1 <= end and nums[child] < nums[child + 1]:  # 右节点比左节点大
            child += 1
        if nums[root] < nums[child]:  # 子节点比父节点大
            nums[root], nums[child] = nums[child], nums[root]  # 交换父子节点
            root = child
        else:
            break

def heapSort(nums):
    # 创建最大堆
    for start in range((len(nums) - 2) // 2, -1, -1):
        heapSift(nums, start, len(nums) - 1)

    # 堆排序
    for end in range(len(nums) - 1, 0, -1):
        nums[0], nums[end] = nums[end], nums[0]  # 将最大值放到最后面
        heapSift(nums, 0, end - 1)  # 对剩下的元素再次进行堆排序

nums = [3, 1, 4, 1, 5, 9, 2, 6, 5, 3, 5]
heapSort(nums)
print(nums)