docs: def finalize(self):
          """finalize for StochasticProcessStatisticsConsumer"""
          super(StochasticProcessStatisticsConsumer, self).finalize()
  
          class StochasticProcessStatistics(self.statistics):
              """local version to store statistics"""
  
              def __str__(self):
                  s = [k.rjust(12) + str(getattr(self, k)) for k in dir(self) if not k.startswith('_')]
                  return '\n'.join(s)
  
          sps = StochasticProcessStatistics([0, 0])
          keys = list()
          for k in dir(sps):
              if not k.startswith('_'):
                  a = getattr(sps, k)
                  if isinstance(a, (int, float, str)):
                      keys.append(k)
                  else:
                      delattr(sps, k)
          for k in keys:
              setattr(sps, k, list())
          grid = list()
          for g, r in self.result:
              grid.append(g)
              for k in keys:
                  a = getattr(sps, k)
                  a.append(getattr(r, k))
          self.result = grid, sps