What are the first and last names of the instructors who teach the top 3 number of courses?
return instructors ;return courses of #1 ;return number of  #2 for each #1 ;return the  3 highest of #3 ;return #1 where #3 is equal to any of #4 ;return first names of #5 ;return last names of #5 ;return #6 ,  #7
['select', 'project', 'group', 'aggregate', 'comparative', 'project', 'project', 'union']