show me flights first class from san francisco to pittsburgh leaving on tuesday after 8 o'clock in the morning and before 12 noon 
return flights ;return #1 that  are first class ;return #2 from san francisco ;return #3 to  pittsburgh ;return #4 that  leave on tuesday ;return #5 after 8 o'clock in the  morning ;return #5 before noon ;return #5 in both #6 and #7
['select', 'filter', 'filter', 'filter', 'filter', 'filter', 'filter', 'intersection']