code: private UnaryCallable<MutateRowsRequest, Void> createMutateRowsBaseCallable() {
      RetryAlgorithm<Void> retryAlgorithm =
          new RetryAlgorithm<>(
              new ApiResultRetryAlgorithm<Void>(),
              new ExponentialRetryAlgorithm(
                  settings.bulkMutateRowsSettings().getRetrySettings(), clientContext.getClock()));
      RetryingExecutorWithContext<Void> retryingExecutor =
          new ScheduledRetryingExecutor<>(retryAlgorithm, clientContext.getExecutor());
  
      return new MutateRowsRetryingCallable(
          clientContext.getDefaultCallContext(),
          stub.mutateRowsCallable(),
          retryingExecutor,
          settings.bulkMutateRowsSettings().getRetryableCodes());
    }
docs: Internal helper to create the base MutateRows callable chain. The chain is responsible for
  retrying individual entry in case of error.
  
  @see MutateRowsRetryingCallable for more details