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

### Instruction:
What was the number of episodes whose production code is 7ABB21?

### Inputs:
table_name: table, columns: ['№', '#', 'Title', 'Directed by', 'Written by', 'Original air date', 'Production code', 'U.S. viewers (millions)']

### Response:
SELECT COUNT # FROM table WHERE Production code = 7ABB21