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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 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)