Show different citizenship of singers and the number of singers of each citizenship.
SELECT Citizenship ,  COUNT(*) FROM singer GROUP BY Citizenship
SELECT Citizenship ,  COUNT(*) FROM singer GROUP BY Citizenship
[{'Citizenship': 'Australia', 'COUNT(*)': 1}, {'Citizenship': 'Chile', 'COUNT(*)': 1}, {'Citizenship': 'France', 'COUNT(*)': 1}, {'Citizenship': 'Germany', 'COUNT(*)': 1}, {'Citizenship': 'United States', 'COUNT(*)': 4}]