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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 _sanity_check_args(args):
 """Ensure dependent arguments are correctly specified """

    if "scheduler" in args and "queue" in args:
        if args.scheduler and not args.queue:
            if args.scheduler != "sge":
                return "IPython parallel scheduler (-s) specified. This also requires a queue (-q)."
        elif args.queue and not args.scheduler:
            return "IPython parallel queue (-q) supplied. This also requires a scheduler (-s)."
        elif args.paralleltype == "ipython" and (not args.queue or not args.scheduler):
            return "IPython parallel requires queue (-q) and scheduler (-s) arguments."