user: Question: What is the highest production code?
Columns: ['No. in series', 'No. in season', 'Title', 'Directed by', 'Written by', 'Original air date', 'Production code', 'U.S. viewers (millions)']
Types: ['real', 'real', 'text', 'text', 'text', 'text', 'real', 'text']
Sample row: [33.0, 1.0, '"The Breakfast Bunch"', 'Steve Hoefer', 'Dan Schneider & Jake Farrow', 'January28,2012', 302.0, '3.9']
SQL:

assistant: SELECT MAX("Production code") FROM "Table";