toJson method
Implementation
core.Map<core.String, core.dynamic> toJson() => {
if (amountInMicros != null) 'amountInMicros': amountInMicros!,
if (currencyCode != null) 'currencyCode': currencyCode!,
if (releaseNumber != null) 'releaseNumber': releaseNumber!,
if (releaseTime != null) 'releaseTime': releaseTime!,
};