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

### Instruction:
Which series had a release on 1939-07-15 with the 8863 production number?

### Inputs:
table_name: table, columns: ['Title', 'Series', 'Director', 'Production Num.', 'Release date']

### Response:
SELECT Series FROM table WHERE Release date = 1939-07-15 AND Production Num. = 8863