code: def hydrate(self, broker=None):
          
          broker = broker or dr.Broker()
          for path in glob(os.path.join(self.meta_data, "*")):
              try:
                  with open(path) as f:
                      doc = ser.load(f)
                      res = self._hydrate_one(doc)
                      comp, results, exec_time, ser_time = res
                      if results:
                          broker[comp] = results
                          broker.exec_times[comp] = exec_time + ser_time
              except Exception as ex:
                  log.warning(ex)
          return broker
docs: Loads a Broker from a previously saved one. A Broker is created if one
          isn't provided.