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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 parent_chain(self):
 """ Return the list of parents starting from this node. The chain ends at the first node with no parents. """

        chain = [self]
        while True:
            try:
                parent = chain[-1].parent
            except Exception:
                break
            if parent is None:
                break
            chain.append(parent)
        return chain