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

### Instruction:
When 5a06 is the production code what is the highest episode?

### Inputs:
table_name: table, columns: ['Ep.', 'Season', 'Title', 'Directed by', 'Written by', 'Original air date', 'Prod. Code']

### Response:
SELECT MAX Ep. FROM table WHERE Prod. Code = 5A06