user: Question: What is the total number of Pick, when Position is ot, when Overall is greater than 91, when Round is greater than 21, and when College is mississippi?
Columns: ['Round', 'Pick', 'Overall', 'Name', 'Position', 'College']
Types: ['real', 'real', 'real', 'text', 'text', 'text']
Sample row: [1.0, 7.0, 7.0, 'Larry Isbell', 'RB', 'Baylor']
SQL:

assistant: SELECT SUM("Pick") FROM "Table" WHERE "Position" = 'ot' AND "Overall" > 91.0 AND "Round" > 21.0 AND "College" = 'mississippi';