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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 get_object_record(self, pid):
 """Get an object that has already been cached in the object tree. Caching happens when the object tree is refreshed. """

        try:
            return self._cache['records'][pid]
        except KeyError:
            raise d1_onedrive.impl.onedrive_exceptions.ONEDriveException('Unknown PID')