You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: processor.go
    path of file: ./repos/benthos/internal/impl/parquet
    
    the code of the file until where you have to start completion: //go:build !arm

package parquet

import (
	"context"
	"fmt"

	"github.com/xitongsys/parquet-go-source/buffer"
	"github.com/xitongsys/parquet-go/parquet"
	"github.com/xitongsys/parquet-go/reader"
	"github.com/xitongsys/parquet-go/writer"

	"github.com/benthosdev/benthos/v4/internal/filepath/ifs"
	"github.com/benthosdev/benthos/v4/public/service"
)

func parquetProcessorConfig() *service.ConfigSpec {
	return service.NewConfigSpec().
		Deprecated().
		Categories("Parsing").
		Summary("Converts batches of documents to or from [Parquet files](https://parquet.apache.org/docs/).").
		Description(`
### Alternatives

This processor is now deprecated, it's recommended that y
    
func (s *parquetProcessor) processBatchReader(ctx context.Context, batch service.MessageBatch) ([]service.MessageBatch, error) {
	if len(batch) == 0 {
		return nil, nil
	}

	outBatches := make([]service.MessageBatch, len(batch))
	for i, m := range batch {
		mBytes, err := m.AsBytes()
		if err != nil {
			return nil, fmt.Errorf("failed to read message contents: %w", err)
		}

		buf := buffer.NewBufferFileFromBytes(mBytes)

		var schema any
		if s.schema != nil {
			schema = *s.schema
		}
		pr, err := reader.NewParquetReader(buf, schema, 1)
		if err != nil {
			return nil, fmt.Errorf("failed to create parquet reader: %w", err)
		}

		var outBatch service.MessageBatch
		for j := 0; j < int(pr.GetNumRows()); j++ {
			res, err := pr.ReadByNumber(j)
			if err != nil {
				return nil, fmt.Errorf("failed to read parquet row: %w", err)
			}
			for _, v := range res {
				outMsg := m.Copy()
				outMsg.SetStructuredMut(v)
				outBatch = append(outBatch, outMsg)
			}
		}

		pr.ReadStop()
		outBatches[i] = outBatch
	}

	return outBatches, nil
}