深浅拷贝
#!/usr/bin/env python
# -*- coding:utf-8 -*-
import copy
# 字符串和数字浅拷贝等价于n2 = n1
n1 = 123
n2 = copy.copy(n1)
print(id(n1))
print(id(n2))
n1 = ['aa', 'bb', ['cc', 'dd']]
n2 = copy.copy(n1)
# 相同
print(id(n1[2]))
print(id(n2[2]))
assert (id(n1[2]) == id(n2[2]))
n2 = copy.deepcopy(n1)
# 不同
print(id(n1[2]))
print(id(n2[2]))
assert not (id(n1[2]) == id(n2[2]))