const a = {
age: 1,
name: 2
}
const b = {
size: 2,
sex: 3
}
const c = Object.assign(a, b)
想实现修改合并后的对象属性值 原对象对应的属性值也改变 ，如何实现

let c = new Proxy({...a, ...b},{
    get: (obj, key) => {
        return obj[key]
    },
    set: (obj, key, value) => {
        if(a.hasOwnProperty(key)) {
            a[key] = value
        }
        if(b.hasOwnProperty(key)) {
            b[key] = value
        }
        obj[key] = value
        return true
    }
})