For each city, what is the highest latitude for its stations?
SELECT city ,  max(lat) FROM station GROUP BY city
SELECT city ,  max(lat) FROM station GROUP BY city
[{'city': 'Mountain View', 'max(lat)': 37.406940000000006}, {'city': 'Palo Alto', 'max(lat)': 37.448598}, {'city': 'Redwood City', 'max(lat)': 37.491269}, {'city': 'San Francisco', 'max(lat)': 37.80477}, {'city': 'San Jose', 'max(lat)': 37.352601}]