How many items are neither metal nor cubes?
return items ;return #1 that  are metal ;return #1 besides #2 ;return #1 that  are cubes ;return #1 besides #4 ;return #1 in both #3 and #5 ;return number of  #6
['select', 'filter', 'discard', 'filter', 'discard', 'intersection', 'aggregate']