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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def get_sub_array_ids(self):
 """Get list of sub array ids"""


        # Initialise empty list
        _scheduling_block_ids = []
        _sub_array_ids = []

        for blocks_id in self.get_sched_block_instance_ids():
            _scheduling_block_ids.append(blocks_id)
        block_details = self.get_block_details(_scheduling_block_ids)
        for details in block_details:
            _sub_array_ids.append(details['sub_array_id'])
        _sub_array_ids = sorted(list(set(_sub_array_ids)))
        return _sub_array_ids