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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_chunk(self, value):
 """Merge pending chunk with next value. :type value: :class:`~google.protobuf.struct_pb2.Value` :param value: continuation of chunked value from previous partial result set. :rtype: :class:`~google.protobuf.struct_pb2.Value` :returns: the merged value """

        current_column = len(self._current_row)
        field = self.fields[current_column]
        merged = _merge_by_type(self._pending_chunk, value, field.type)
        self._pending_chunk = None
        return merged