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

### Instruction:
Who directed the episodes that aired December 15, 1956?

### Inputs:
table_name: table, columns: ['Series #', 'Season #', 'Title', 'Director', 'Writer(s)', 'Airdate']

### Response:
SELECT Director FROM table WHERE Airdate = December 15, 1956