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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 _verify_consent(self, consent_id):
 """ Connects to the consent service using the REST api and checks if the user has given consent :type consent_id: str :rtype: Optional[List[str]] :param consent_id: An id associated to the authenticated user, the calling requester and attributes to be sent. :return: list attributes given which have been approved by user consent """

        request = "{}/verify/{}".format(self.api_url, consent_id)
        res = requests.get(request)

        if res.status_code == 200:
            return json.loads(res.text)

        return None