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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 _iter_interleaved_items(self, elements):
 """Generate element or subtotal items in interleaved order. This ordering corresponds to how value "rows" (or columns) are to appear after subtotals have been inserted at their anchor locations. Where more than one subtotal is anchored to the same location, they appear in their document order in the cube response. Only elements in the passed *elements* collection appear, which allows control over whether missing elements are included by choosing `.all_elements` or `.valid_elements`. """

        subtotals = self._subtotals

        for subtotal in subtotals.iter_for_anchor("top"):
            yield subtotal

        for element in elements:
            yield element
            for subtotal in subtotals.iter_for_anchor(element.element_id):
                yield subtotal

        for subtotal in subtotals.iter_for_anchor("bottom"):
            yield subtotal