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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 barrier(events, sid, kind='neighbour'):
 """ act as a multiprocessing barrier """

    events[sid].set()
    # only wait for the neighbours
    if kind=='neighbour':
        if sid > 0:
            logging.debug("{0} is waiting for {1}".format(sid, sid - 1))
            events[sid - 1].wait()
        if sid < len(bkg_events) - 1:
            logging.debug("{0} is waiting for {1}".format(sid, sid + 1))
            events[sid + 1].wait()
    # wait for all
    else:
        [e.wait() for e in events]
    return