public boolean isUnavailable(Node node) {
        return NetworkClientUtils.isUnavailable(client, node, time);
    }
Check if the node is disconnected and unavailable for immediate reconnection (i.e. if it is in
reconnect backoff window following the disconnect).

@param node {@link Node} to check for availability
@see NetworkClientUtils#isUnavailable(KafkaClient, Node, Time)
clients/src/main/java/org/apache/kafka/clients/consumer/internals/NetworkClientDelegate.java