user: ### NOW ANSWER:
Question: What is the name of the national final co host when David Jacobs was the National final main host, and the selection show was A Song For Europe in 1966?
Columns: ['Year(s)', 'Selection show', 'Venue', 'National final main host', 'National final co host', 'Semi final/heat host']
Types: ['text', 'text', 'text', 'text', 'text', 'text']
Sample row: ['1956', 'UK did not participate', 'UK did not participate', 'UK did not participate', 'UK did not participate', 'UK did not participate']
SQL:

assistant: SELECT "National final co host" FROM "Table" WHERE "National final main host" = 'David Jacobs' AND "Selection show" = 'A Song For Europe' AND "Year(s)" = '1966';