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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 _patchDatetimeMetadata( self, res, mk ):
 """Private method to patch an ISO datetime string to a datetime object for metadata key mk. :param res: results dict :param mk: metadata key"""

        t = res[epyc.Experiment.METADATA][mk]
        res[epyc.Experiment.METADATA][mk] = dateutil.parser.parse(t)