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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 _update_result(self, result, insertions, dimension_index):
 """Insert subtotals into resulting ndarray."""

        for j, (ind_insertion, value) in enumerate(insertions):
            result = np.insert(
                result, ind_insertion + j + 1, value, axis=dimension_index
            )
        return result