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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 logical_definitions(self, nid):
 """ Retrieves logical definitions for a class id Arguments --------- nid : str Node identifier for entity to be queried Returns ------- LogicalDefinition """

        ldefs = self.all_logical_definitions
        if ldefs is not None:
            #print("TESTING: {} AGAINST LD: {}".format(nid, str(ldefs)))
            return [x for x in ldefs if x.class_id == nid]
        else:
            return []