python的轮询timer 和js的轮询setInterval

python的轮询Timer：                                                                        

import threading
def say_hello(arg=''):
    timer_online = threading.Timer(1, say_hello,('world',))
    timer_online.start()
    print('hello ',arg)

say_hello()

---

js中的轮询setInterval：                                                                

<script type="text/javascript">
    var timer1 = 1;
    window.onload = function () {
        function read_data() {
            location.href = 'http://127.0.0.1:8000';
        };
        timer1 = window.setInterval(read_data,2*1000);
    };
        $('#begin_btn').click(function () {
            location.href = 'http://127.0.0.1:8000';
        });
        $('#cancle_btn').click(function () {
            window.clearInterval(timer1);
        })
</script>