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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 log_level_type(arg):
 	"""An argparse type representing a logging level."""

	if not arg.upper() in ('NOTSET', 'DEBUG', 'INFO', 'WARNING', 'ERROR', 'CRITICAL'):
		raise argparse.ArgumentTypeError("{0} is not a valid log level".format(repr(arg)))
	return getattr(logging, arg.upper())