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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 dedent(self, node, dirty=True):
 """Dedent an item. Does nothing if the target is not indented under this item. Args: node (gkeepapi.node.ListItem):
 Item to dedent. dirty (bool):
 Whether this node should be marked dirty. """

        if node.id not in self._subitems:
            return

        del self._subitems[node.id]
        node.super_list_item_id = None
        node.parent_item = None
        if dirty:
            node.touch(True)