code: def _sort_lambda(sortedby='cpu_percent',
                   sortedby_secondary='memory_percent'):
      
      ret = None
      if sortedby == 'io_counters':
          ret = _sort_io_counters
      elif sortedby == 'cpu_times':
          ret = _sort_cpu_times
      return ret
docs: Return a sort lambda function for the sortedbykey