def _update_day_dict(self, data_point, day_dict):
        """
        Helper method for :meth:`_print_daily_stats`. Given a data point and
        the correct day dict, update attribs on the dict with the contents
        of the data point.
        
        :param dict data_point: The data point to add to the day's stats dict.
        :param dict day_dict: A stats-tracking dict for a 24 hour period.
        """
        for topic in ['Bounces', 'Complaints', 'DeliveryAttempts', 'Rejects']:
            day_dict[topic] = day_dict.get(topic, 0) + int(data_point[topic])
Helper method for :meth:`_print_daily_stats`. Given a data point and
        the correct day dict, update attribs on the dict with the contents
        of the data point.
        
        :param dict data_point: The data point to add to the day's stats dict.
        :param dict day_dict: A stats-tracking dict for a 24 hour period.