There are two objects of the same shape and color; what shape are they?
return objects ;return shapes of #1 ;return colors of #1 ;return #1 where #2 are the  same ;return #1 where #3 are the  same ;return #1 in both #4 and #5 ;return the  shape of #6
['select', 'project', 'project', 'comparative', 'comparative', 'intersection', 'project']