user: Question: Who was the contstructor of the car having a grid of 20?
Columns: ['Driver', 'Constructor', 'Laps', 'Time/Retired', 'Grid']
Types: ['text', 'text', 'text', 'text', 'text']
Sample row: ['Felipe Massa', 'Ferrari', '57', '1:31:06.970', '2']
SQL:

assistant: SELECT "Constructor" FROM "Table" WHERE "Grid" = '20';