我是Go的新手。我開始編寫我的第一個代碼，我必須從AWS下載一堆CSV。我不明白為什么它給我以下錯誤與O_APPEND模式。如果我刪除 ，我只得到最后一個文件數據，這不是目標。os.O_APPEND目標是將所有 CSV 文件下載到本地的一個文件中。我想了解我做錯了什么。package mainimport (    "fmt"    "os"    "path/filepath"    "github.com/aws/aws-sdk-go/aws"    "github.com/aws/aws-sdk-go/aws/credentials"    "github.com/aws/aws-sdk-go/aws/session"    "github.com/aws/aws-sdk-go/service/s3"    "github.com/aws/aws-sdk-go/service/s3/s3manager")const (    AccessKeyId     = "xxxxxxxxx"    SecretAccessKey = "xxxxxxxxxxxxxxxxxxxx"    Region          = "eu-central-1"    Bucket          = "dexter-reports"    bucketKey       = "Jenkins/pluginVersions/")func main() {    // Load the Shared AWS Configuration    os.Setenv("AWS_ACCESS_KEY_ID", AccessKeyId)    os.Setenv("AWS_SECRET_ACCESS_KEY", SecretAccessKey)    filename := "JenkinsPluginDetais.txt"    cred := credentials.NewStaticCredentials(AccessKeyId, SecretAccessKey, "")    config := aws.Config{Credentials: cred, Region: aws.String(Region), Endpoint: aws.String("s3.amazonaws.com")}    file, err := os.OpenFile(filename, os.O_APPEND|os.O_WRONLY|os.O_CREATE, 0666)    if err != nil {        panic(err)    }    defer file.Close()    sess, err := session.NewSession(&config)    if err != nil {        fmt.Println(err)    }    //list Buckets    ObjectList := listBucketObjects(sess)    //loop over the obectlist. First initialize the s3 downloader via s3manager    downloader := s3manager.NewDownloader(sess)    for _, item := range ObjectList.Contents {        csvFile := filepath.Base(*item.Key)        if csvFile != "pluginVersions" {            downloadBucketObjects(downloader, file, csvFile)        }    }}func listBucketObjects(sess *session.Session) *s3.ListObjectsV2Output {    //create a new s3 client    svc := s3.New(sess)    resp, err := svc.ListObjectsV2(&s3.ListObjectsV2Input{        Bucket: aws.String(Bucket),        Prefix: aws.String(bucketKey),    })    if err != nil {        panic(err)    }    return resp}