JSFiddle - React, Tailwind, and code Playground

HTML

<form action="./cgi-bin/my_script.py" method="post" enctype="multipart/form-data" name="fname">
    <input type="submit" id="submit" value="Submit" />
</form>    
<div id='content'></div>

CSS

#loading { display:none; }

JavaScript

$(document).ready(function() {
    $("form").submit(function(e) {
        e.preventDefault();
        $('#content').html('put your loading html here').load('/ajax_html_echo/', function(response, status, xhr) {
            //This is the callback. You can check for error here.
            //For example if (status == 'error') alertTheMedia();
        });
    });
});