If a single seal is standing on top of a rock with its mouth open.
return seal ;return rock ;return #1 that is standing on top of #2 ;return mouth of #3 ;return #3 where  #4 is open ;return number of  #5 ;return if  #6 is equal to  one
['select', 'select', 'filter', 'project', 'comparative', 'aggregate', 'boolean']