show me first class round trip flights from new york to miami i want the cheapest first class fare please 
return flights ;return #1 in first  class  ;return #2 that  are round trip ;return #3 from  new york ;return #4 to miami ;return fares of #5 ;return cheapest of #6
['select', 'filter', 'filter', 'filter', 'filter', 'project', 'project']