SynthesisInput constructor
      
      SynthesisInput({ 
    
    
- CustomPronunciations? customPronunciations,
- String? markup,
- MultiSpeakerMarkup? multiSpeakerMarkup,
- String? prompt,
- String? ssml,
- String? text,
Implementation
SynthesisInput({
  this.customPronunciations,
  this.markup,
  this.multiSpeakerMarkup,
  this.prompt,
  this.ssml,
  this.text,
});