How to use the oss2.Service function in oss2

def clean_and_delete_bucket_by_prefix(bucket_prefix):
    service = oss2.Service(oss2.Auth(OSS_ID, OSS_SECRET), OSS_ENDPOINT)
    buckets = service.list_buckets(prefix=bucket_prefix).buckets
    for b in buckets:
        bucket = oss2.Bucket(oss2.Auth(OSS_ID, OSS_SECRET), b.extranet_endpoint, b.name)
        clean_and_delete_bucket(bucket)

assert_found = False
            def do_request(session_self, req, timeout):
                if assert_found:
                    self.assertTrue(req.headers['User-Agent'].find(app) >= 0)
                else:
                    self.assertTrue(req.headers['User-Agent'].find(app) < 0)

                raise oss2.exceptions.ClientError('intentional')

            from unittest.mock import patch
            with patch.object(oss2.Session, 'do_request', side_effect=do_request, autospec=True):
                # 不加 app_name
                assert_found = False
                self.assertRaises(oss2.exceptions.ClientError, self.bucket.get_bucket_acl)

                service = oss2.Service(oss2.Auth(OSS_ID, OSS_SECRET), OSS_ENDPOINT)
                self.assertRaises(oss2.exceptions.ClientError, service.list_buckets)

                # 加app_name
                assert_found = True
                bucket = oss2.Bucket(oss2.Auth(OSS_ID, OSS_SECRET), OSS_ENDPOINT, OSS_BUCKET,
                                     app_name=app)
                self.assertRaises(oss2.exceptions.ClientError, bucket.get_bucket_acl)

                service = oss2.Service(oss2.Auth(OSS_ID, OSS_SECRET), OSS_ENDPOINT,
                                       app_name=app)
                self.assertRaises(oss2.exceptions.ClientError, service.list_buckets)

def test_bucket_iterator(self):
        service = oss2.Service(oss2.Auth(OSS_ID, OSS_SECRET), OSS_ENDPOINT)
        self.assertTrue(OSS_BUCKET in (b.name for b in oss2.BucketIterator(service, max_keys=2)))
        self.assertTrue(OSS_BUCKET in list(b.name for b in oss2.BucketIterator(service, max_keys=2)))

from unittest.mock import patch
            with patch.object(oss2.Session, 'do_request', side_effect=do_request, autospec=True):
                # 不加 app_name
                assert_found = False
                self.assertRaises(oss2.exceptions.ClientError, self.bucket.get_bucket_acl)

                service = oss2.Service(oss2.Auth(OSS_ID, OSS_SECRET), OSS_ENDPOINT)
                self.assertRaises(oss2.exceptions.ClientError, service.list_buckets)

                # 加app_name
                assert_found = True
                bucket = oss2.Bucket(oss2.Auth(OSS_ID, OSS_SECRET), OSS_ENDPOINT, OSS_BUCKET,
                                     app_name=app)
                self.assertRaises(oss2.exceptions.ClientError, bucket.get_bucket_acl)

                service = oss2.Service(oss2.Auth(OSS_ID, OSS_SECRET), OSS_ENDPOINT,
                                       app_name=app)
                self.assertRaises(oss2.exceptions.ClientError, service.list_buckets)

def oss_check(self, bucket_name, default_endpoint, access_key_id, access_key_secret):
        if bucket_name in self.bucket_endpoints:
            endpoint = self.bucket_endpoints[bucket_name]
            try:
                bucket = oss2.Bucket(oss2.Auth(access_key_id, access_key_secret), endpoint, bucket_name, connect_timeout=5.0, app_name=defaults.app_name)
                res = bucket.get_bucket_acl()
            except oss2.exceptions.OssError as e:
                raise AuthenticationFailed("access bucket:%s using specified \
                        endpoint:%s failed. request_id:%s, status:%s, code:%s, message:%s" % (bucket_name, endpoint, e.request_id, unicode(e.status), e.code, e.message))
            return endpoint 
        try:
            service = oss2.Service(oss2.Auth(access_key_id, access_key_secret), default_endpoint, app_name=defaults.app_name)
            res = service.list_buckets(prefix=bucket_name)
        except oss2.exceptions.AccessDenied as e:
            raise AuthenticationFailed("can't list buckets, check your access_key.request_id:%s, status:%s, code:%s, message:%s"% (e.request_id, unicode(e.status), e.code, e.message))
        except oss2.exceptions.OssError as e:
            raise AuthenticationFailed("list buckets error. request_id:%s, status:%s, code:%s, message:%s" % (e.request_id, unicode(e.status), e.code, e.message))

        bucket_list = res.buckets
        for bucket in bucket_list:
            if bucket.name == bucket_name:
                endpoint = self.get_endpoint(bucket_name, bucket.location.decode('utf-8'), access_key_id, access_key_secret)
                return endpoint
        raise AuthenticationFailed("can't find the bucket %s when list buckets." % bucket_name)

def get_oss_client(credentials, region=None):
    try:
        auth = oss2.Auth(credentials.credentials.access_key_id, credentials.credentials.access_key_secret)
        client = oss2.Service(auth,
                              endpoint='oss-{}.aliyuncs.com'.format(region) if region
                              else 'oss-cn-hangzhou.aliyuncs.com')
        return client

    except Exception as e:
        print_exception(e)
        return None

def __init__(self):
        self.access_key_id = self._get_config('OSS_ACCESS_KEY_ID')
        self.access_key_secret = self._get_config('OSS_ACCESS_KEY_SECRET')
        self.end_point = _normalize_endpoint(self._get_config('OSS_END_POINT').strip())
        self.bucket_name = self._get_config('OSS_BUCKET_NAME')
        self.cname = self._get_config('OSS_CNAME')

        self.auth = Auth(self.access_key_id, self.access_key_secret)
        self.service = Service(self.auth, self.end_point)

        try:
            if self.bucket_name not in self._list_bucket(self.service):
                # create bucket if not exists
                self.bucket = self._create_bucket(self.auth)
            else:
                # change bucket acl if not consists
                self.bucket = self._check_bucket_acl(self._get_bucket(self.auth))
        except AccessDenied:
            # 当启用了RAM访问策略，是不允许list和create bucket的
            self.bucket = self._get_bucket(self.auth)