JSFiddle - React, Tailwind, and code Playground

JavaScript

function addScript(fileSrc, callback) {
  var head = document.getElementsByTagName('head')[0];
  var script = document.createElement('script');
  script.type = 'text/javascript';
  script.onreadystatechange = function() {
    if (this.readyState == 'complete')
      callback();
  }
  script.onload = callback;
  script.src = fileSrc;
  head.appendChild(script);
}
var src = 'https://api.clicky.com/api/stats/4?site_id=32020&sitekey=9a19b1a4d1171193&type=visitors&date=this-month&output=json&json_callback=my_callback';
my_callback = function(someData) {
    alert(JSON.stringify(someData));
  };
addScript(src, function(data) {
  console.log('data is ', my_callback);
  var visitors_loaded = false;
  if (visitors_loaded) return 0;
  if (data) {
    //success: callback function is called and it has a proper data
    visitors_loaded = true;
  } else alert('error'); //something went wrong
});