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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 leaves_not_empty(self):
 """ Return the list of leaves not empty in the tree rooted at this node, in DFS order. :rtype: list of :class:`~aeneas.tree.Tree` """

        return [n for n in self.dfs if ((n.is_leaf) and (not n.is_empty))]