user: Question: Total enrollment at the school with the nickname Blue Hens
Columns: ['Institution', 'Location', 'Nickname', 'Enrollment', 'Established']
Types: ['text', 'text', 'text', 'real', 'real']
Sample row: ['University of Delaware', 'Newark, DE', 'Blue Hens', 19391.0, 1743.0]
SQL:

assistant: SELECT "Enrollment" FROM "Table" WHERE "Nickname" = 'Blue Hens';