How to use the pymemcache.client.base.PooledClient function in pymemcache

def make_client_pool(self, hostname, mock_socket_values, serializer=None, **kwargs):
        mock_client = pymemcache.client.base.Client(
            hostname, serializer=serializer, **kwargs
        )
        tracer = get_dummy_tracer()
        Pin.override(mock_client, tracer=tracer)

        mock_client.sock = MockSocket(mock_socket_values)
        client = pymemcache.client.base.PooledClient(hostname, serializer=serializer)
        client.client_pool = pymemcache.pool.ObjectPool(lambda: mock_client)
        return mock_client

def setUp(self):
        pool = PooledClient(server=memcached_endpoint.address)
        self.backend_factory = MemcacheRateLimitBackendContextFactory(pool)
        super().setUp()

def add_server(self, server, port):
        key = '%s:%s' % (server, port)

        if self.use_pooling:
            client = PooledClient(
                (server, port),
                **self.default_kwargs
            )
        else:
            client = Client((server, port), **self.default_kwargs)

        self.clients[key] = client
        self.hasher.add_node(key)

:returns: :py:class:`pymemcache.client.base.PooledClient`

    """
    assert prefix.endswith(".")
    parser = config.SpecParser(
        {
            "endpoint": config.Endpoint,
            "max_pool_size": config.Optional(config.Integer, default=None),
            "connect_timeout": config.Optional(config.TimespanWithLegacyFallback, default=None),
            "timeout": config.Optional(config.TimespanWithLegacyFallback, default=None),
            "no_delay": config.Optional(config.Boolean, default=True),
        }
    )
    options = parser.parse(prefix[:-1], app_config)

    return PooledClient(
        server=options.endpoint.address,
        connect_timeout=options.connect_timeout and options.connect_timeout.total_seconds(),
        timeout=options.timeout and options.timeout.total_seconds(),
        serializer=serializer,
        deserializer=deserializer,
        no_delay=options.no_delay,
        max_pool_size=options.max_pool_size,
    )