user: Question: What is the visitor team on April 4?
Columns: ['Date', 'Visitor', 'Score', 'Home', 'Record']
Types: ['text', 'text', 'text', 'text', 'text']
Sample row: ['April 4', 'St. Louis Blues', '1–7', 'Chicago Black Hawks', '1-0']
SQL:

assistant: SELECT "Visitor" FROM "Table" WHERE "Date" = 'April 4';