js_arch.py

def sender(request):
    if not request.is_ajax():
        raise Http404

    #import ipdb; ipdb.set_trace()
    images = Image.objects.filter(is_available=True).order_by('last_update')

    if images:
        image = images[0]
        image.is_available = False
        image.save()
        if not request.user.is_anonymous():
            UserImage(image=image, sender=request.user).save()

    # List of functions to be executed
    result = []
    result.append(
            {'selector': '#panel',
             'content': render_response(request, "_sender.html", dict(image=image if image else '')).content,
             'call_function': 'change_content'}
            )
    return HttpResponse(simplejson.dumps(result))


# ----------------------- JAVASCRIPT ---------------------- #
function process_callbacks(data){
    for(var i=0;i<data.length;i++){
        if($functions[data[i].call_function])
            $functions[data[i].call_function](data[i].selector,data[i].content);
        else
            alert('Error, no existe '+data[i].call_function);
    }
}