code: def print_benchmark(self):
          
          print('%-7.2f %s' % (self.elapsed, 'seconds elapsed'))
          if self.elapsed:
              for key in self._benchmark_keys:
                  print('%-7d %s per second (%d total)' %
                        (self.counters[key] / self.elapsed, key,
                         self.counters[key]))
docs: Print benchmark numbers.