If at least one of the houses has exactly two chimney stacks.
return houses ;return chimney stacks ;return the  number of  #2 for each  #1 ;return #1 where  #3 is equal to  two ;return the  number of  #4 ;return if  #5 is at least one
['select', 'select', 'group', 'comparative', 'aggregate', 'boolean']