user: Question: What is the production number of 3-04?
Columns: ['Episode No.', 'Prod No.', 'Title', 'Directed by', 'Written by', 'Original airdate UK']
Types: ['text', 'real', 'text', 'text', 'text', 'text']
Sample row: ['3-01', 67.0, '"The Black Book"', 'Michael Truman', 'Philip Broadley', 'September 30, 1965']
SQL:

assistant: SELECT "Prod No." FROM "Table" WHERE "Episode No." = '3-04';