code: def stats(self, alpha=0.05, start=0, batches=100,
                chain=None, quantiles=(2.5, 25, 50, 75, 97.5)):
          
          return self.trace.stats(alpha=alpha, start=start, batches=batches,
                                  chain=chain, quantiles=quantiles)
docs: Generate posterior statistics for node.
  
          :Parameters:
          alpha : float
            The alpha level for generating posterior intervals. Defaults to
            0.05.
  
          start : int
            The starting index from which to summarize (each) chain. Defaults
            to zero.
  
          batches : int
            Batch size for calculating standard deviation for non-independent
            samples. Defaults to 100.
  
          chain : int
            The index for which chain to summarize. Defaults to None (all
            chains).
  
          quantiles : tuple or list
            The desired quantiles to be calculated. Defaults to (2.5, 25, 50, 75, 97.5).