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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 siblings(self):
 """ Tuple of nodes with the same parent. () () (Node('/Udo/Marc/Loui'), Node('/Udo/Marc/Lazy')) (Node('/Udo/Marc/Lian'), Node('/Udo/Marc/Lazy')) """

        parent = self.parent
        if parent is None:
            return tuple()
        else:
            return tuple([node for node in parent.children if node != self])