如何根据python3中元素的值将平面列表转换为列表列表？

def convert_list(lst):
    result = []
    sublist = []
    previous_value = None
    
    for element in lst:
        if element != previous_value:
            sublist = [element]
            result.append(sublist)
        else:
            sublist.append(element)
        
        previous_value = element
    
    return result

flat_list = [1, 1, 2, 3, 3, 4, 5, 5, 5]
nested_list = convert_list(flat_list)
print(nested_list)

[[1, 1], [2], [3, 3], [4], [5, 5, 5]]