show me flights first class from san francisco to pittsburgh leaving on tuesday after 8 o'clock in the morning and before 12 noon
O O O B-class_type I-class_type O B-fromloc.city_name I-fromloc.city_name O B-toloc.city_name O O B-depart_date.day_name B-depart_time.time_relative B-depart_time.time I-depart_time.time O O B-depart_time.period_of_day O B-depart_time.time_relative B-depart_time.time I-depart_time.time