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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 create_attribute_response(self, identity, in_response_to, destination, sp_entity_id, userid="", name_id=None, status=None, issuer=None, sign_assertion=False, sign_response=False, attributes=None, sign_alg=None, digest_alg=None, farg=None, **kwargs):
 """ Create an attribute assertion response. :param identity: A dictionary with attributes and values that are expected to be the bases for the assertion in the response. :param in_response_to: The session identifier of the request :param destination: The URL which should receive the response :param sp_entity_id: The entity identifier of the SP :param userid: A identifier of the user :param name_id: The identifier of the subject :param status: The status of the response :param issuer: The issuer of the response :param sign_assertion: Whether the assertion should be signed or not :param sign_response: Whether the whole response should be signed :param attributes: :param kwargs: To catch extra keyword arguments :return: A response instance """


        policy = self.config.getattr("policy", "aa")

        if not name_id and userid:
            try:
                name_id = self.ident.construct_nameid(userid, policy,
                                                      sp_entity_id)
                logger.warning("Unspecified NameID format")
            except Exception:
                pass

        to_sign = []

        if identity:
            farg = self.update_farg(in_response_to, sp_entity_id, farg=farg)

            _issuer = self._issuer(issuer)
            ast = Assertion(identity)
            if policy:
                ast.apply_policy(sp_entity_id, policy, self.metadata)
            else:
                policy = Policy()

            if attributes:
                restr = restriction_from_attribute_spec(attributes)
                ast = filter_attribute_value_assertions(ast)

            assertion = ast.construct(
                sp_entity_id, self.config.attribute_converters, policy,
                issuer=_issuer, name_id=name_id,
                farg=farg['assertion'])

            if sign_assertion:
                assertion.signature = pre_signature_part(assertion.id,
                                                         self.sec.my_cert, 1,
                                                         sign_alg=sign_alg,
                                                         digest_alg=digest_alg)
                # Just the assertion or the response and the assertion ?
                to_sign = [(class_name(assertion), assertion.id)]
                kwargs['sign_assertion'] = True

            kwargs["assertion"] = assertion

        if sp_entity_id:
            kwargs['sp_entity_id'] = sp_entity_id

        return self._response(in_response_to, destination, status, issuer,
                              sign_response, to_sign, sign_alg=sign_alg,
                              digest_alg=digest_alg, **kwargs)