toJson method
Implementation
Map<String, dynamic> toJson() => {
if (replacement_id != null) 'replacement_id': replacement_id,
if (target_user != null) 'target_user': target_user!.toJson(),
if (create_call != null) 'create_call': create_call,
if (await_call != null) 'await_call': await_call,
if (target_room != null) 'target_room': target_room,
};