Sorry, but not completely in the way you want. But you could set up a lab environment for yourself where you make libraries a little quicker to load by giving it a short name and fetch the libraries via cdnjs, they have reasonably predictable URL path names.
The function would look a bit like this:
window.jsopen = function(path) {
var el = document.createElement('script');
if(path.indexOf('http') == 0) {
el.src = path;
} else {
el.src = '//cdnjs.cloudflare.com/ajax/libs/'+path;
}
document.head.appendChild(el);
}
Embed that in a piece of simple HTML and open developer tools, and open the CDNJS site in a tab beside it. Now you should be able to import libraries either by their full URL, or by the final part of their path there. With jQuery in your example it would be reduced to:
> jsopen('jquery/2.0.3/jquery.min.js')
undefined
> $
function (e,n){return new x.fn.init(e,n,t)}
It's still nothing like what you could get on Python, but it's a little bit better than doing the whole thing as you describe in your question.
Also notice that the function doesn't (can't) know about dependencies, so:
> jsopen('backbone.js/1.1.2/backbone-min.js')
undefined
Uncaught TypeError: Cannot call method 'each' [...]
but:
> jsopen('underscore.js/1.6.0/underscore-min.js')
undefined
> jsopen('backbone.js/1.1.2/backbone-min.js')
undefined
> Backbone
Object {VERSION: "1.1.2", $: function,
Advanced version: you can make a lab environment that do know about dependencies with a combination of Browserify and NPM.