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

### Instruction:
In which years are co-stars  mala sinha and amitabh bachchan?

### Inputs:
table_name: table, columns: ['Song', 'Singer', 'Co-Singers', 'Music Director', 'Lyricist', 'Co-Stars', 'Movie/Album', 'Year', 'Additional Info']

### Response:
SELECT Year FROM table WHERE Co-Stars = Mala Sinha and Amitabh Bachchan