toJson method
Implementation
@override
Map<String, dynamic> toJson() => <String, dynamic>{
'photo': photo?.toJson(),
'thumbnail': thumbnail?.toJson(),
'video': video?.toJson(),
'added_sticker_file_ids': addedStickerFileIds.map((item) => item).toList(),
'width': width,
'height': height,
'@type': constructor,
};