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: universal_redis_store.go
    path of file: ./repos/seaweedfs/weed/filer/redis3
    
    the code of the file until where you have to start completion: package redis3

import (
	"context"
	"fmt"
	"time"

	"github.com/go-redis/redis/v8"

	redsync "github.com/go-redsync/redsync/v4"
	"github.com/seaweedfs/seaweedfs/weed/filer"
	"github.com/seaweedfs/seaweedfs/weed/glog"
	"github.com/seaweedfs/seaweedfs/weed/pb/filer_pb"
	"github.com/seaweedfs/seaweedfs/weed/util"
)

const (
	DIR_LIST_MARKER = "\x00"
)

type UniversalRedis3Store struct {
	Client  redis.UniversalClient
	redsync *redsync.Redsync
}

func (store *UniversalRedis3Store) BeginTransaction(ctx context.Context) (context.Context, error)
    
func (store *UniversalRedis3Store) DeleteFolderChildren(ctx context.Context, fullpath util.FullPath) (err error) {

	return removeChildren(ctx, store, genDirectoryListKey(string(fullpath)), func(name string) error {
		path := util.NewFullPath(string(fullpath), name)
		_, err = store.Client.Del(ctx, string(path)).Result()
		if err != nil {
			return fmt.Errorf("DeleteFolderChildren %s in parent dir: %v", fullpath, err)
		}
		// not efficient, but need to remove if it is a directory
		store.Client.Del(ctx, genDirectoryListKey(string(path)))
		return nil
	})

}