instruction: what flights are available tuesday afternoon from PITTSBURGH to ATLANTA
response: SELECT DISTINCT flight.flight_id FROM airport_service AS AIRPORT_SERVICE_0, airport_service AS AIRPORT_SERVICE_1, city AS CITY_0, city AS CITY_1, date_day, days, flight WHERE ((CITY_1.city_code = AIRPORT_SERVICE_1.city_code AND CITY_1.city_name = 'ATLANTA' AND date_day.day_number = 22 AND date_day.month_number = 3 AND date_day.year = 1991 AND days.day_name = date_day.day_name AND flight.flight_days = days.days_code AND flight.to_airport = AIRPORT_SERVICE_1.airport_code) AND CITY_0.city_code = AIRPORT_SERVICE_0.city_code AND CITY_0.city_name = 'PITTSBURGH' AND flight.from_airport = AIRPORT_SERVICE_0.airport_code) AND flight.departure_time BETWEEN 1200 AND 1800