user: Question: What was the format for the 4 disc season that had less than 22 episodes and N/A for region 4?
Columns: ['DVD Season', 'Format', '# Episodes', '# Disc(s)', 'Region 4']
Types: ['text', 'text', 'real', 'real', 'text']
Sample row: ['The Complete Season 1', 'DVD', 22.0, 6.0, '2December2009']
SQL:

assistant: SELECT "Format" FROM "Table" WHERE "# Episodes" < 22.0 AND "# Disc(s)" = 4.0 AND "Region 4" = 'N/A';