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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_occur(self, node, value):
 """Propagate occurence `value` to `node` and its ancestors. Occurence values are defined and explained in the SchemaNode class. """

        while node.occur < value:
            node.occur = value
            if node.name == "define":
                break
            node = node.parent