def edit_wiki_page(self, subreddit, page, content, reason=''):
        """Create or edit a wiki page with title `page` for `subreddit`.

        :returns: The json response from the server.

        """
        data = {'content': content,
                'page': page,
                'r': six.text_type(subreddit),
                'reason': reason}
        evict = self.config['wiki_page'].format(
            subreddit=six.text_type(subreddit), page=page.lower())
        self.evict(evict)
        return self.request_json(self.config['wiki_edit'], data=data)