tts, err := tiktok_tts.TTS(tiktok_tts.VoiceEnglishFem1, "Hello World")
    if err != nil { /* ... */ }

    buf, err := base64.StdEncoding.DecodeString(tts.Data.VStr)
    if err != nil { /* ... */ }
    // buf now contains MP3 file data which can be written to a file