outgoing.go
func (oa *OutgoingAudio) querystring() querystring {
	toReturn := map[string]string(oa.getBaseQueryString())

	if oa.Duration != 0 {
		toReturn["duration"] = fmt.Sprint(oa.Duration)
	}

	if oa.Performer != "" {
		toReturn["performer"] = oa.Performer
	}

	if oa.Title != "" {
		toReturn["title"] = oa.Title
	}

	return querystring(toReturn)
}
func (oa *OutgoingAudio) querystring() querystring {
	toReturn := map[string]string(oa.getBaseQueryString())

	if oa.Duration != 0 {
		toReturn["duration"] = fmt.Sprint(oa.Duration)
	}

	if oa.Performer != "" {
		toReturn["performer"] = oa.Performer
	}

	if oa.Title != "" {
		toReturn["title"] = oa.Title
	}

	return querystring(toReturn)
}
// querystring implements querystringer to represent the audio file.