对象深拷贝 面试题

写一个对象，实现深度拷贝
https://developer.mozilla.org/zh-CN/docs/Web/JavaScript/Reference/Global_Objects/Object/assign

for in

let obj = {
 name:'小明',
 age:24 
} 
let obj1=clone(obj);

function clone(obj){
  let _obj={};
  for(let key in obj){
    _obj[key] = obj[key];
  }
  return _obj;
}

Object.assign

function clone(obj){
  return Object.assign({},obj);
}

function clone(obj){
  return JSON.parse(JSON.stringify(obj))
}