user: Question: What is the issue price of a Year 2000 coin by artist John Mardon of the Included in Steam Buggy mintage.
Columns: ['Year', 'Theme', 'Artist', 'Mintage', 'Issue Price']
Types: ['real', 'text', 'text', 'text', 'text']
Sample row: [2000.0, 'Steam Buggy', 'John Mardon', '44,367', '$59.95']
SQL:

assistant: SELECT "Issue Price" FROM "Table" WHERE "Artist" = 'John Mardon' AND "Year" = 2000.0 AND "Mintage" = 'Included in Steam Buggy';