user: Question: What is Country, when Player is Billy Mayfair?
Columns: ['Place', 'Player', 'Country', 'Score', 'To par']
Types: ['text', 'text', 'text', 'text', 'text']
Sample row: ['1', 'Tiger Woods', 'United States', '67-68=135', '–5']
SQL:

assistant: SELECT "Country" FROM "Table" WHERE "Player" = 'Billy Mayfair';