user: Question: What is the largest number of episodes for a 1989 season dvd release? 
Columns: ['DVD Title', 'No. of Discs', 'Year', 'No. of Episodes', 'Region 1', 'Region 2', 'Region 4']
Types: ['text', 'real', 'text', 'real', 'text', 'text', 'text']
Sample row: ['Series 1', 4.0, '1978', 13.0, '14 May 2002', 'N/A', '2 January 2013']
SQL:

assistant: SELECT MAX("No. of Episodes") FROM "Table" WHERE "Year" = '1989';