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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 get_property_chain_axioms(self, nid):
 """ Retrieves property chain axioms for a class id Arguments --------- nid : str Node identifier for relation to be queried Returns ------- PropertyChainAxiom """

        pcas = self.all_property_chain_axioms
        if pcas is not None:
            return [x for x in pcas if x.predicate_id == nid]
        else:
            return []