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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 change_prior(self, **kwargs):
 """ Changes existing priorfactors. If given keyword isn't already in priorfactors, then will be ignored. """

        for kw in kwargs:
            if kw in self.priorfactors:
                self.priorfactors[kw] = kwargs[kw]
                logging.info('{0} changed to {1} for {2} model'.format(kw,kwargs[kw],
                                                                       self.model))