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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 others(self):
 """Iterate over all nodes of the tree excluding one self and one's children."""

        if not self.parent: return
        yield self.parent
        for sibling in self.parent.children.values():
            if sibling.name == self.name: continue
            for node in sibling: yield node
        for node in self.parent.others: yield node