<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def run(self, manager):
 """Run this query and returns the resulting BEL graph. :param manager: A cache manager :rtype: Optional[pybel.BELGraph] """

        universe = self._get_universe(manager)
        graph = self.seeding.run(universe)
        return self.pipeline.run(graph, universe=universe)