What is the average age and how many male students are there in each city?
return cities ;return students in #1 ;return ages of #2 ;return average of #3 ;return #2 that  are male ;return number of  #5 for each #1 ;return #4 ,  #6
['select', 'project', 'project', 'aggregate', 'filter', 'group', 'union']