Get a serializable dict of the instance of this class.
        :return:

def get_serializable_dict(self):
        """
        Get a serializable dict of the instance of this class.
        :return:
        """
        tmp = self.get_dict()
        tmp['date_download'] = str(tmp['date_download'])
        tmp['date_modify'] = str(tmp['date_modify'])
        tmp['date_publish'] = str(tmp['date_publish'])
        return tmp