Does the leftmost item share a shape with any other item?
return items ;return #1 that are the  leftmost ;return #1 besides  #2 ;return shape of #2 ;return shapes of #3 ;return #3 where #5 is the  same as #4 ;return number of  #6 ;return if #7 is at least one
['select', 'filter', 'discard', 'project', 'project', 'comparative', 'aggregate', 'boolean']