Below is an instruction that describes a task. Write a response that appropriately completes the request.

### Instruction:
What is the turnout with 15 candidates and more than 377,591 valid poll?

### Inputs:
table_name: table, columns: ['Constituency', 'Electorate', 'Turnout', 'Spoilt', 'Valid Poll', 'Quota', 'Seats', 'Candidates']

### Response:
SELECT Turnout FROM table WHERE Candidates = 15 AND Valid Poll > 377,591