instruction: flights from MILWAUKEE to PHOENIX on saturday or sunday AA
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 AS DATE_DAY_0, date_day AS DATE_DAY_1, days AS DAYS_0, days AS DAYS_1, flight WHERE (((flight.airline_code = 'AA') AND ((flight.flight_days = DAYS_0.days_code AND DAYS_0.day_name = DATE_DAY_0.day_name AND DATE_DAY_0.year = 1991 AND DATE_DAY_0.month_number = 7 AND DATE_DAY_0.day_number = 26) OR (flight.flight_days = DAYS_1.days_code AND DAYS_1.day_name = DATE_DAY_1.day_name AND DATE_DAY_1.year = 1991 AND DATE_DAY_1.month_number = 7 AND DATE_DAY_1.day_number = 26))) AND CITY_1.city_code = AIRPORT_SERVICE_1.city_code AND CITY_1.city_name = 'PHOENIX' AND flight.to_airport = AIRPORT_SERVICE_1.airport_code) AND CITY_0.city_code = AIRPORT_SERVICE_0.city_code AND CITY_0.city_name = 'MILWAUKEE' AND flight.from_airport = AIRPORT_SERVICE_0.airport_code