1.在python中，对象赋值实际上是对象的引用。当创建一个对象，然后把它赋给另一个变量的时候，python并没有拷贝这个对象，而只是拷贝了这个对象的引用

（1）直接赋值,默认浅拷贝传递对象的引用而已,原始列表改变，被赋值的b也会做相同的改变

# -*- coding: utf-8 -*-if __name__ == '__main__':b = [1, 2, 3]a = bprint(a)print(b)a.append(4)print(a)print(b)

（2）copy浅拷贝，没有拷贝子对象，所以原始数据改变，子对象会改变

# -*- coding: utf-8 -*-
import copyif __name__ == '__main__':b = [1, 2, ["hello", "word"]]a = copy.copy(b)print(a)print(b)a.append(4)print(a)print(b)b[2].append("鸿蒙2.0")print(a)print(b)

运行结果：

"C:\Program Files\Python38\python.exe" E:/PythonSourceCode/test/main.py
[1, 2, ['hello', 'word']]
[1, 2, ['hello', 'word']]
[1, 2, ['hello', 'word'], 4]
[1, 2, ['hello', 'word']]
[1, 2, ['hello', 'word', '鸿蒙2.0'], 4]       这里数据变了
[1, 2, ['hello', 'word', '鸿蒙2.0']]

（3）深拷贝，包含对象里面的自对象的拷贝，所以原始对象的改变不会造成深拷贝里任何子元素的改变

# -*- coding: utf-8 -*-
import copyif __name__ == '__main__':b = [1, 2, ["hello", "word"]]a = copy.deepcopy(b)print(a)print(b)b[2].append("鸿蒙2.0")print(a)print(b)

运行结果：

"C:\Program Files\Python38\python.exe" E:/PythonSourceCode/test/main.py
[1, 2, ['hello', 'word']]
[1, 2, ['hello', 'word']]
[1, 2, ['hello', 'word']]
[1, 2, ['hello', 'word', '鸿蒙2.0']]