Pass in an iterator of tweets' JSON and get back an iterator of the
        IDs of each tweet.

def dehydrate(self, iterator):
        """
        Pass in an iterator of tweets' JSON and get back an iterator of the
        IDs of each tweet.
        """
        for line in iterator:
            try:
                yield json.loads(line)['id_str']
            except Exception as e:
                log.error("uhoh: %s\n" % e)