Find the name of captains whose rank are either Midshipman or Lieutenant.
return captains ;return ranks of  #1 ;return #1 where  #2 is  Midshipman ;return #1 where  #2 is  Lieutenant ;return #3 or  #4 ;return names of  #5
['select', 'project', 'comparative', 'comparative', 'union', 'project']