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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 _propagate(self, path, val):
 """ Propagate the value up to the root node. """

        if val == '_DELETE':
            if path in self.data:
                del self.data[path]
            else:
                items = [(key, v) for key, v in self.data.items()
                         if not all(k==p for k, p in zip(key, path))]
                self.data = OrderedDict(items)
        else:
            self.data[path] = val
        if self.parent is not None:
            self.parent._propagate((self.identifier,)+path, val)