写一个方法对对象中的key进行排序

Object.prototype.sortedKeys = function() {    const thisKeys = []    for (const key in this) {        if (Object.prototype.hasOwnProperty.call(this, key)) { thisKeys.push(key)        }    }    thisKeys.sort()    return thisKeys}

a = {name: 'name', aName: 'aname', zName: 'zname'}a.sortedKeys()// ["aName", "name", "zName"]