code: func (builder *SSMLTextBuilder) AppendPhoneme(alphabet PhoneticAlphabet, phoneme, text string) *SSMLTextBuilder {
  
  	if phoneme != "" && text != "" && alphabet != PhoneticAlphabet("") {
  		builder.buffer.WriteString(fmt.Sprintf("<phoneme alphabet=\"%s\" ph=\"%s\">%s</phoneme>", alphabet, phoneme, text))
  	}
  
  	return builder
  }
docs: // AppendPhoneme is used to specify a phonetic pronunciation for a piece of text to be appended
  // to the response.