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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 _merge_meta(self, encoded_meta, meta):
 """ Merge new meta dict into encoded meta. Returns new encoded meta. """

        new_meta = None

        if meta:
            _meta = self._decode_meta(encoded_meta)
            for key, value in six.iteritems(meta):
                if value is None:
                    _meta.pop(key, None)
                else:
                    _meta[key] = value
            new_meta = self._encode_meta(_meta)

        return new_meta