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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 iter_up(self, include_self=True):
 """Iterates up the tree to the root."""

        if include_self: yield self
        parent = self.parent
        while parent is not None:
            yield parent
            try:
                parent = parent.parent
            except AttributeError:
                return