toJson method
Implementation
core.Map<core.String, core.dynamic> toJson() => {
if (audioEncoding != null) 'audioEncoding': audioEncoding!,
if (sampleRateHertz != null) 'sampleRateHertz': sampleRateHertz!,
if (synthesizeSpeechConfig != null)
'synthesizeSpeechConfig': synthesizeSpeechConfig!,
};