code: func NewEtcdConnectionUsingClient(etcdClient *clientv3.Client, log logging.Logger) (*BytesConnectionEtcd, error) {
  	conn := BytesConnectionEtcd{
  		Logger:     log,
  		etcdClient: etcdClient,
  		lessor:     clientv3.NewLease(etcdClient),
  		opTimeout:  defaultOpTimeout,
  	}
  	return &conn, nil
  }
docs: // NewEtcdConnectionUsingClient creates a new instance of BytesConnectionEtcd
  // using the provided etcd client.
  // This constructor is used primarily for testing.