user: Question: What is the mean pick when the play is marc lewis (lhp) and the round is less than 20?
Columns: ['Round', 'Pick', 'Player', 'Nationality', 'School']
Types: ['real', 'real', 'text', 'text', 'text']
Sample row: [1.0, 12.0, 'Matt Dominguez (3B)', 'United States', 'Chatsworth High School']
SQL:

assistant: SELECT AVG("Pick") FROM "Table" WHERE "Player" = 'marc lewis (lhp)' AND "Round" < 20.0;