Fetches all of the given object from the graph.

        We return a map from ID to object. If any of the IDs are
        invalid, we raise an exception.

def get_objects(self, ids, **args):
        """Fetches all of the given object from the graph.

        We return a map from ID to object. If any of the IDs are
        invalid, we raise an exception.
        """
        args["ids"] = ",".join(ids)
        return self.request(self.version + "/", args)