IPython extension snippet: Add answer buttons

answer_buttons.js

"using strict";
var answer_buttons = (function() {

    function add_buttons(){
        console.log("runit");
        $("div").each( function(){
            if (this.className === 'answer') {
                var button= '<input type="button" value="Answer" onclick="showHide(' + this.id + ')">';
                this.insertAdjacentHTML("beforeBegin",button);
            }
        });
    };

$([IPython.events]).on('notebook_loaded.Notebook',add_buttons());

    IPython.toolbar.add_buttons_group([
                {
                    id : 'add_buttons',
                    label : 'Add answer buttons',
                    icon : 'icon-list-alt',
                    callback : add_buttons
                }
          ]);
          
})();

function showHide(e) {
   if(e.style.display == 'block')
      e.style.display = 'none';
   else
      e.style.display = 'block';
}

If anyone still wondering, simply enable "Exercise" and "Exercise 2" extension for your jupyter notebook will do now.