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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 inserted_hs_indices(self):
 """list of int index of each inserted subtotal for the dimension. Each value represents the position of a subtotal in the interleaved sequence of elements and subtotals items. """

        # ---don't do H&S insertions for CA and MR subvar dimensions---
        if self.dimension_type in DT.ARRAY_TYPES:
            return []

        return [
            idx
            for idx, item in enumerate(
                self._iter_interleaved_items(self.valid_elements)
            )
            if item.is_insertion
        ]