user: Question: Which pre-season has May 5 of 21?
Columns: ['Poll', 'Pre- season', 'Mar. 3', 'May 5', 'May 12', 'May 19', 'May 26', 'Final Poll']
Types: ['text', 'text', 'text', 'text', 'text', 'text', 'text', 'text']
Sample row: ["USA Today/ESPN Coaches' Poll (Top 25)", 'NR', 'NR', '22', '21', '13', '7', '6']
SQL:

assistant: SELECT "Pre- season" FROM "Table" WHERE "May 5" = '21';