Saves frames data into a json file at the
        specified json_path, named with the widget uuid.

def save_json(self, frames):
        """
        Saves frames data into a json file at the
        specified json_path, named with the widget uuid.
        """
        if self.json_save_path is None: return
        path = os.path.join(self.json_save_path, '%s.json' % self.id)
        if not os.path.isdir(self.json_save_path):
            os.mkdir(self.json_save_path)
        with open(path, 'w') as f:
            json.dump(frames, f)
        self.json_data = frames