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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 _accumulate_kvstore(self, key, value):
 """Accumulate gradients over all data in the KVStore. In distributed setting, each worker sees a portion of data. The full gradients will be aggregated from each worker in the KVStore. Parameters key: int or str Key in the KVStore. value: NDArray, RowSparseNDArray Average of the full gradients. """

        # Accumulate full gradients for current epochs
        self._kvstore.push(key + "_full", value)
        self._kvstore._barrier()
        self._kvstore.pull(key + "_full", value)

        self._allocate_gradients(key, value)