请将以下行程信息转换为CSV格式，每行一条行程：
date,type,fromCode,toCode,fromStation,toStation,flightNo,trainNo,airline,depTime,arrTime,seatClass,seatType,seat,price

字段：date(YYYY-MM-DD), type(flight/train), fromCode/toCode(机场IATA如PEK), fromStation/toStation(高铁站名), flightNo(航班号), trainNo(车次), airline(二字码CA/MU/CZ/HO/3U), depTime/arrTime(HH:MM), seatClass(economy/business/first), seatType(second/first/business), seat(座位号), price(票价数字)

示例：
date,type,fromCode,toCode,fromStation,toStation,flightNo,trainNo,airline,depTime,arrTime,seatClass,seatType,seat,price
2025-06-15,flight,SHA,PEK,,,CA1234,,CA,08:00,10:15,economy,,,580
2025-06-20,train,,,上海虹桥,杭州东,,G7501,,09:00,10:05,,second,5车12A,73

只输出CSV，不要其他解释。