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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 replaceItemAtIndex(self, newItem, oldItemIndex):
 """ Removes the item at the itemIndex and insert a new item instead. """

        oldItem = self.getItem(oldItemIndex)
        childNumber = oldItem.childNumber()
        parentIndex = oldItemIndex.parent()
        self.deleteItemAtIndex(oldItemIndex)
        insertedIndex = self.insertItem(newItem, position=childNumber, parentIndex=parentIndex)
        return insertedIndex