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: backup_txn.go
    path of file: ./repos/tidb/br/pkg/task
    
    the code of the file until where you have to start completion: // Copyright 2020 PingCAP, Inc. Licensed under Apache-2.0.

package task

import (
	"bytes"
	"context"

	"github.com/opentracing/opentracing-go"
	"github.com/pingcap/errors"
	backuppb "github.com/pingcap/kvproto/pkg/brpb"
	"github.com/pingcap/log"
	"github.com/pingcap/tidb/br/pkg/backup"
	"github.com/pingcap/tidb/br/pkg/conn"
	berrors "github.com/pingcap/tidb/br/
    
func DefineTxnBackupFlags(command *cobra.Command) {
	command.Flags().StringP(flagStartKey, "", "", "backup txn kv start key, key is inclusive")
	command.Flags().StringP(flagEndKey, "", "", "backup txn kv end key, key is exclusive")
	command.Flags().Int64P(flagStartVersion, "", 0, "backup timestamp for txn kv")
	command.Flags().String(flagCompressionType, "zstd",
		"backup sst file compression algorithm, value can be one of 'lz4|zstd|snappy'")
	command.Flags().Bool(flagRemoveSchedulers, false,
		"disable the balance, shuffle and region-merge schedulers in PD to speed up backup")
	// This flag can impact the online cluster, so hide it in case of abuse.
	_ = command.Flags().MarkHidden(flagRemoveSchedulers)
}