Return the colleges that have players who play the Midfielder position, as well as players who play the Defender position.
return colleges ;return players  of  #1 ;return positions of  #2 ;return #1 where  #3 is Midfielder ;return #1 where  #3 is Defender ;return #1 of  both #4 and #5
['select', 'project', 'project', 'comparative', 'comparative', 'intersection']