I am really sorry if the question already exists, but I have been searching everywhere for 30 minutes with no result. So I am wondering if I can see the actual javascript code, which is linked in the script tag, so I can learn from it. For example, I am really curious to take a look at this javascript code:
<script src="https://smart-ip.net/geoip-json?callback=ip_callback"></script>
Yes, you can. Just copy its url and paste it in your browser's address bar.