toJson method
Implementation
core.Map<core.String, core.dynamic> toJson() => {
if (endTime != null) 'endTime': endTime!,
if (priceChangeBehavior != null)
'priceChangeBehavior': priceChangeBehavior!,
if (releaseTime != null) 'releaseTime': releaseTime!,
if (startTime != null) 'startTime': startTime!,
};