def sortProperties(self, properties):  # modified to sort objects using their global rank
        """Take a hash from predicate uris to lists of values.
           Sort the lists of values.  Return a sorted list of properties."""
        # Sort object lists
        for prop, objects in properties.items():
            objects.sort(key=self._globalSortKey)

        # Make sorted list of properties
        return sorted(properties, key=lambda p: self.predicate_rank[p])
Take a hash from predicate uris to lists of values.
           Sort the lists of values.  Return a sorted list of properties.