toJson method
Implementation
core.Map<core.String, core.dynamic> toJson() => {
if (endClosed != null) 'endClosed': endClosed!,
if (endOpen != null) 'endOpen': endOpen!,
if (startClosed != null) 'startClosed': startClosed!,
if (startOpen != null) 'startOpen': startOpen!,
};