code: def spawn_missing_master(self):
          '''
          Notifies the standalone slave agency that the master agency is missing
          '''
          d = defer.succeed(None)
          if callable(self.on_master_missing_cb):
              d.addCallback(defer.drop_param, self.on_master_missing_cb)
          return f spawn_missing_master(self):
          '''
          Notifies the standalone slave agency that the master agency is missing
          '''
          d = defer.succeed(None)
          if callable(self.on_master_missing_cb):
              d.addCallback(defer.drop_param, self.on_master_missing_cb)
          return d
docs: Notifies the standalone slave agency that the master agency is missing