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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 set_attachments_order(self, order):
 """Remember the attachments order """

        # append single uids to the order
        if isinstance(order, basestring):
            new_order = self.storage.get("order", [])
            new_order.append(order)
            order = new_order
        self.storage.update({"order": order})