const obj={
            "0":'xm',
            'sex':'male',
            length:2
        }
        obj[Symbol.iterator]=()=>{
            let index=0;
            return {
                next(){
                    index++;
                    if(index==1){
                        value=obj[0],
                        done=false
                    }else if(index==2){
                        value=obj.sex;
                        done=false
                    }else{
                        done=true
                    }
                    return {
                        value,done
                    }
                }
            }
        }
        for(let item of obj){
            console.log(item);
        }