googleapi：错误403：请求的身份验证范围不足。详细信息：原因：权限不足，消息：权限不足

我正在尝试使用Gmail API发送电子邮件。但是我得到这个错误

googleapi：错误403：请求的身份验证范围不足。详细信息：原因：权限不足，消息：权限不足

我认为这可能与config有关，我还遵循了Google的Go快速入门，这里是getClient函数：

func getClient(config *oauth2.Config) *http.Client {
    // The file token.json stores the user's access and refresh tokens, and is
    // created automatically when the authorization flow completes for the first
    // time.
    tokFile := "token.json"
    tok, err := tokenFromFile(tokFile)

    if err != nil {
            tok = getTokenFromWeb(config)
            saveToken(tokFile, tok)
    }
    return config.Client(context.Background(), tok)
}

这是发送的代码：

case "pass":
    
    templateData := struct {
        VerPass string
        
    }{
        VerPass: cont1,
        
    }

    emailBody, err := parseTemplate("ver.html", templateData)
    if err != nil {
        fmt.Println("Parse Err")
        return false, err
     }
     
    var message gmail.Message
 
    emailTo := "To: " + to + "\r\n"
    subject := "Subject: " + sub + "\n"
    mime := "MIME-version: 1.0;\nContent-Type: text/html; charset=\"UTF-8\";\n\n"
    msg := []byte(emailTo + subject + mime + "\n" + emailBody)
 
    message.Raw = base64.URLEncoding.EncodeToString(msg)
 
    // Send the message
    fmt.Println("OOOOOYYYYY")
    //here is the problem
    b, err := ioutil.ReadFile("credentials.json")
if err != nil {
        log.Fatalf("Unable to read client secret file: %v", err)
}

// If modifying these scopes, delete your previously saved token.json.
config, err := google.ConfigFromJSON(b, gmail.MailGoogleComScope)

if err != nil {
        log.Fatalf("Unable to parse client secret file to config: %v", err)
}
    client := getClient(config)

srv, err := gmail.New(client)
if err != nil {
        log.Fatalf("Unable to retrieve Gmail client: %v", err)
}
//GmailService
    res, err := srv.Users.Messages.Send("me", &message).Do() // change me
    if err != nil {
        fmt.Println("Res Err")
        fmt.Println(err)
       return false, err
    }
    fmt.Println(res)

我尝试过for config, err := google.ConfigFromJSON(b, gmail.MailGoogleComScope)，尝试使用GmailReadonlyScope和gmail.GmailSendScope，但是遇到了同样的错误。