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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 apply(cls, args, run):
 """Add priority info for this run."""

        try:
            priority = float(args)
        except ValueError:
            raise ValueError("The PRIORITY argument must be a number! "
                             "(but was '{}')".format(args))
        run.meta_info['priority'] = priority