<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def get_active() -> List[str]: """Return the list of active subarrays."""

        active = []
        for i in range(__num_subarrays__):
            key = Subarray.get_key(i)
            if DB.get_hash_value(key, 'active').upper() == 'TRUE':
                active.append(Subarray.get_id(i))
        return active