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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 _authn_response(self, context):
 """ Handles the authentication response from the AS. :type context: satosa.context.Context :rtype: satosa.response.Response :param context: The context in SATOSA :return: A SATOSA response. This method is only responsible to call the callback function which generates the Response object. """

        state_data = context.state[self.name]
        aresp = self.consumer.parse_response(AuthorizationResponse, info=json.dumps(context.request))
        self._verify_state(aresp, state_data, context.state)

        rargs = {"code": aresp["code"], "redirect_uri": self.redirect_url,
                 "state": state_data["state"]}

        atresp = self.consumer.do_access_token_request(request_args=rargs, state=aresp["state"])
        if "verify_accesstoken_state" not in self.config or self.config["verify_accesstoken_state"]:
            self._verify_state(atresp, state_data, context.state)

        user_info = self.user_information(atresp["access_token"])
        internal_response = InternalData(auth_info=self.auth_info(context.request))
        internal_response.attributes = self.converter.to_internal(self.external_type, user_info)
        internal_response.subject_id = user_info[self.user_id_attr]
        del context.state[self.name]
        return self.auth_callback_func(context, internal_response)