Python-追加到对象列表内的对象列表[重复]

Question

此问题已经在这里有了答案：

“Least Astonishment” and the Mutable Default Argument（31个答案）

[<6天前关闭。

以下面的示例：

from pprint import pprint
class ResultsClass:
    def __init__(self, 
    name = None, 
    counts = []): 
        self.name = name
        self.counts = counts

objs = [ResultsClass() for i in range(5)]
i = 0 
while i < 4:
    objs[i].counts.append("count is " + str(i))
    pprint(objs[i].counts)
    i = i+1

结果是：
['count is 0']
['count is 0', 'count is 1']
['count is 0', 'count is 1', 'count is 2']
['count is 0', 'count is 1', 'count is 2', 'count is 3']

我也尝试了以下代码无济于事：
i = 0
objs = [ResultsClass() for i in range(5)]
for obj in objs:
    obj.counts.append("count is " + str(i))
    pprint(obj.counts)
    i = +1

我想做的是让每个ResultsClass实例具有不同的
counts列表，如下所示：
['count is 0'] 
['count is 1'] 
['count is 2'] 
['count is 3']

来自PowerShell的背景，我本来以为Python会遍历对象的每个实例并附加到其中的特定列表；相反，它似乎是附加到对象列表和
counts属性的所有实例之后。 
获得理想结果的最佳方法是什么？ 

Answer 1