def get_confidence(self, url=None, article_id=None):
        """
        Send a GET request to the `confidence` endpoint of the Parser API.

        Note that either the `url` or `article_id` param should be passed.

        :param url (optional): The url of an article whose content is wanted.
        :param article_id (optional): The id of an article in the Readability
            system whose content is wanted.
        """
        query_params = {}
        if url is not None:
            query_params['url'] = url
        if article_id is not None:
            query_params['article_id'] = article_id
        url = self._generate_url('confidence', query_params=query_params)
        return self.get(url)
Send a GET request to the `confidence` endpoint of the Parser API.

        Note that either the `url` or `article_id` param should be passed.

        :param url (optional): The url of an article whose content is wanted.
        :param article_id (optional): The id of an article in the Readability
            system whose content is wanted.