instruction: please give me flight schedules from BALTIMORE to PHILADELPHIA
response: SELECT DISTINCT FLIGHT_0.arrival_time, FLIGHT_0.departure_time FROM airport_service AS AIRPORT_SERVICE_0, airport_service AS AIRPORT_SERVICE_1, city AS CITY_0, city AS CITY_1, flight AS FLIGHT_0, flight AS FLIGHT_1, flight_leg WHERE CITY_0.city_code = AIRPORT_SERVICE_0.city_code AND CITY_0.city_name = 'BALTIMORE' AND CITY_1.city_code = AIRPORT_SERVICE_1.city_code AND CITY_1.city_name = 'PHILADELPHIA' AND FLIGHT_0.flight_id = flight_leg.leg_flight AND FLIGHT_1.flight_id = flight_leg.flight_id AND FLIGHT_1.from_airport = AIRPORT_SERVICE_0.airport_code AND FLIGHT_1.to_airport = AIRPORT_SERVICE_1.airport_code