[web2py] ajax update database

[comamitc]

I am wondering the best way to send more than one record's value to a
controller and then update a database with it.  What i want to do is
push a string like:

var data = "[{"id": 1, "val": something},{"id": 2, "val":
somethingElse}]";

into:

$.ajax({
        type: "POST",
        url: fetchURL("saveAttrs"),
        data: attr_data,
// everything below here is unimportant!!!
        success: function(msg){
                                        $("li#stats").show().html(msg);
                                        setTimeout(clearStats, 3000);
                                                        }
});

I am unsure of how to access this data from the server side. I tried
an example on stackoverflow which was:

def saveAttrs():
     import simplejson as json
     j = json.loads(request.body.read())
     return "success!"

but this gave me an error saying my string wasn't JSON formatted.  How
exaclty do i get this data to the server in bulk format instead of
having to update every record independently in the jQuery for each
loop.

Thanks in advance!