user: Question: What was the first day cover cancellation for the University of Saskatchewan themed stamp?
Columns: ['Date of Issue', 'Theme', 'Denomination', 'Design', 'Illustration', 'Printing Process', 'Paper Type', 'First Day Cover Cancellation']
Types: ['text', 'text', 'text', 'text', 'text', 'text', 'text', 'text']
Sample row: ['5 January 2007', 'Year of the Pig', '52 cents', 'John Belisle, Kosta Tsetsekas', 'John Belisle', 'Lithography in 8 colours with two foil stampings', 'Tullis Russell Coatings', 'Toronto, ON']
SQL:

assistant: SELECT "First Day Cover Cancellation" FROM "Table" WHERE "Theme" = 'University of Saskatchewan';