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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 abort (aggregate):
 """Helper function to ensure a clean shutdown."""

    while True:
        try:
            aggregate.abort()
            aggregate.finish()
            aggregate.end_log_output(interrupt=True)
            break
        except KeyboardInterrupt:
            log.warn(LOG_CHECK, _("user abort; force shutdown"))
            aggregate.end_log_output(interrupt=True)
            abort_now()