If three parrots have red feathered heads and white beaks.
return parrots ;return heads of #1 ;return #1 where  #2 are red feathered ;return beaks of #3 ;return #3 where  #4 are white ;return number of  #5 ;return if  #6 is equal to  three
['select', 'project', 'comparative', 'project', 'comparative', 'aggregate', 'boolean']