To embed this as a third part script, use the following code:
(function(h,e,k,o){
h[o]||(function(){var t=e.createElement(k);
var als=e.getElementsByTagName(k)[0];
t.src='//cdn.rawgit.com/bl4ckdu5t/sparro-js/cb8f0792/heko.js';
t.async = true;
als.parentNode.insertBefore(t,als);
}());
}(window, document, 'script', 'hk'));
//hk('key', 'A3JKFD98B');hk('group', 'hipster');