深浅拷贝

深拷贝

• 复制后的内容改变，原来的列表不受影响
• copy.deepcopy()

浅拷贝

• 复制后的内容改变，原来的列表也受影响
• 只会复制顶层对象，不影响深层的可变数据类型
• copy.copy()

import copy
num = [1,2,3,[1,2]]
num_new = copy.copy(num)
print(num_new)
num_new.append(5)
print(num)
print(num_new)
num_new[3][0] = 3
print(num)
print(num_new)


import copy
num = [1,2,3,[1,2]]
num_new = copy.deepcopy(num)
print(num_new)
num_new.append(5)
print(num)
print(num_new)
num_new[3][0] = ：3
print(num)
print(num_new)
输出：
[1, 2, 3, [1, 2]]
[1, 2, 3, [1, 2]]
[1, 2, 3, [1, 2], 5]
[1, 2, 3, [3, 2]]
[1, 2, 3, [3, 2], 5] #改变列表中的列表，原列表跟着改变
[1, 2, 3, [1, 2]]
[1, 2, 3, [1, 2]]
[1, 2, 3, [1, 2], 5]
[1, 2, 3, [1, 2]]
[1, 2, 3, [3, 2], 5] #改变列表中的列表，原列表不改变