def _mark_as_read(self, thing_ids, unread=False):
        """Mark each of the supplied thing_ids as (un)read.

        :returns: The json response from the server.

        """
        data = {'id': ','.join(thing_ids)}
        key = 'unread_message' if unread else 'read_message'
        response = self.request_json(self.config[key], data=data)
        self.evict([self.config[x] for x in ['inbox', 'messages',
                                             'mod_mail', 'unread']])
        return response