copy深浅拷贝
import copy # 浅拷贝 # copy.copy() # 深拷贝 # copy.deepcopy() # 赋值 s1 = '1234' s2 = 456 t1 = s1 t2 = s2 c1 = copy.copy(s1) c2 = copy.deepcopy(s1) print(id(s1), id(t1), id(c1), id(c2), id(s2), id(t2)) # 浅拷贝 l1 = ['1234', 'fhgo', (1, 3, 4, 5), [1, 2, 3, 4], {'a': 'a', 'b': 'b'}] l2 = copy.copy(l1) print(id(l1), id(l2)) ''' 浅拷贝只在新内存空间拷贝了l1最外层, 所以l2的元素[3]地址还是l1的元素地址 , 那么在l1的原有元素[3]地址改变内容, l2也会改变, l1的新增元素, 则不会影响l2 ''' l1[3].append(5) l1[0] = 'aaa' print(l1, l2, id(l1[3]), id(l2[3]), 'l1原有元素3新增5,影响了l2的元素3') l1.append(6) print(l1, l2, 'l1新增6没影响l2') # 深拷贝 l1 = ['1234', 'fhgo', (1, 3, 4, 5), [1, 2, 3, 4], {'a': 'a', 'b': 'b'}] l2 = copy.deepcopy(l1) ''' 深拷贝在新空间地址,将l1每层元素都拷贝(字符串和数字,不会拷贝),所以改变l1不会改变l2 ''' l1[3].append(5) l1[0]='aaa' print(l1, l2, id(l1[0]), id(l2[0]), 'l1原有元素3新增5,没影响l2的元素3') l1.append(6) print(l1, l2, 'l1新增6没影响l2') exit()