What is the average age and how many male students are there in each city?
SELECT count(*) ,  avg(age) ,  city_code FROM student WHERE sex  =  'M' GROUP BY city_code
SELECT count(*) ,  avg(age) ,  city_code FROM student WHERE sex  =  'M' GROUP BY city_code
[{'count(*)': 1, 'avg(age)': 20.0, 'city_code': 'ATL'}, {'count(*)': 1, 'avg(age)': 18.0, 'city_code': 'BAL'}, {'count(*)': 1, 'avg(age)': 18.0, 'city_code': 'BOS'}, {'count(*)': 1, 'avg(age)': 20.0, 'city_code': 'CHI'}, {'count(*)': 1, 'avg(age)': 18.0, 'city_code': 'DAL'}, {'count(*)': 1, 'avg(age)': 17.0, 'city_code': 'DET'}, {'count(*)': 1, 'avg(age)': 19.0, 'city_code': 'HKG'}, {'count(*)': 1, 'avg(age)': 17.0, 'city_code': 'HOU'}, {'count(*)': 1, 'avg(age)': 27.0, 'city_code': 'LON'}, {'count(*)': 1, 'avg(age)': 18.0, 'city_code': 'LOS'}, {'count(*)': 1, 'avg(age)': 18.0, 'city_code': 'NAR'}, {'count(*)': 3, 'avg(age)': 20.333333333333332, 'city_code': 'NYC'}, {'count(*)': 1, 'avg(age)': 17.0, 'city_code': 'PEK'}, {'count(*)': 2, 'avg(age)': 19.5, 'city_code': 'PHL'}, {'count(*)': 3, 'avg(age)': 19.333333333333332, 'city_code': 'PIT'}, {'count(*)': 1, 'avg(age)': 20.0, 'city_code': 'ROC'}, {'count(*)': 1, 'avg(age)': 18.0, 'city_code': 'WAS'}, {'count(*)': 2, 'avg(age)': 22.5, 'city_code': 'YYZ'}]