user: Question: What is Opponent, when Location is "Tokyo , Japan", when Method is "Decision (unanimous)", and when Record is "4-1"?
Columns: ['Res.', 'Record', 'Opponent', 'Method', 'Event', 'Round', 'Location']
Types: ['text', 'text', 'text', 'text', 'text', 'text', 'text']
Sample row: ['Win', '20-8', 'Giovani Diniz', 'TKO (punches)', 'Shooto - 5th Round', '1', 'Tokyo , Japan']
SQL:

assistant: SELECT "Opponent" FROM "Table" WHERE "Location" = 'Tokyo , Japan' AND "Method" = 'Decision (unanimous)' AND "Record" = '4-1';