code: def push_pq(self, tokens):
          
          logger.debug("Pushing PQ data: %s" % tokens)
  
          bus = self.case.buses[tokens["bus_no"] - 1]
          bus.p_demand = tokens["p"]
          bus.q_demand = tokens["q"]
docs: Creates and Load object, populates it with data, finds its Bus and
          adds it.