如何使用Go在远程机器上执行命令？

func remoteRun(user string, addr string, privateKey string, cmd string) (string, error) {
    // Parse the private key and configure the SSH client
    key, err := ssh.ParsePrivateKey([]byte(privateKey))
    if err != nil {
        return "", err
    }
    config := &ssh.ClientConfig{
        User: user,
        HostKeyCallback: ssh.InsecureIgnoreHostKey(),
        Auth: []ssh.AuthMethod{
            ssh.PublicKeys(key),
        },
    }

    // Connect to the remote machine
    client, err := ssh.Dial("tcp", net.JoinHostPort(addr, "22"), config)
    if err != nil {
        return "", err
    }

    // Create a new session
    session, err := client.NewSession()
    if err != nil {
        return "", err
    }
    defer session.Close()

    // Capture stdout for the command
    var b bytes.Buffer
    session.Stdout = &b

    // Execute the command and return the output
    err = session.Run(cmd)
    return b.String(), err
}