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

### Instruction:
Who was the director when the writer was John Sullivan?

### Inputs:
table_name: table, columns: ['Episode', 'Original title', 'Directed by', 'Written by', 'Original airdate', 'Duration', 'Viewership']

### Response:
SELECT Directed by FROM table WHERE Written by = John Sullivan