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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 _scheduling_block_config(num_blocks=5, start_sbi_id=0, start_pb_id=0, project='sip'):
 """Return a Scheduling Block Configuration dictionary"""

    pb_id = start_pb_id
    for sb_id, sbi_id in _scheduling_block_ids(num_blocks, start_sbi_id,
                                               project):
        sub_array_id = 'subarray-{:02d}'.format(random.choice(range(5)))
        config = dict(id=sbi_id,
                      sched_block_id=sb_id,
                      sub_array_id=sub_array_id,
                      processing_blocks=_generate_processing_blocks(pb_id))
        pb_id += len(config['processing_blocks'])
        yield config