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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 _local_update(self, rdict):
 """Call this with a response dictionary to update instance attrs. If the response has only valid keys, stash meta_data, replace __dict__, and reassign meta_data. :param rdict: response attributes derived from server JSON """

        sanitized = self._check_keys(rdict)
        temp_meta = self._meta_data
        self.__dict__ = sanitized
        self._meta_data = temp_meta