def individual_billed_ops_to_str(self):
  return billed_ops_to_str(self.billed_ops_list())
apply an autoregressive filter to a series x
dataset/ETHPy150Open AppScale/appscale/AppServer/google/appengine/ext/appstats/recording.py/individual_billed_ops_to_str--crossover with--dataset/ETHPy150Open statsmodels/statsmodels/statsmodels/tsa/varma_process.py/varfilter