code: def main(argv=None):
      
      import getopt
  
      # default values
      test_read = None
      test_write = None
      n = 3       # number of repeat
  
      if argv is None:
          argv = sys.argv[1:]
  
      try:
          opts, args = getopt.getopt(argv, 'hn:rw', [])
  
          for o,a in opts:
              if o == '-h':
                  print(HELP)
                  return 0
              elif o == '-n':
                  n = int(a)
              elif o == '-r':
                  test_read = True
              elif o == '-w':
                  test_write = True
  
          if args:
              raise getopt.GetoptError('Arguments are not used.')
      except getopt.GetoptError:
          msg = sys.exc_info()[1]     # current exception
          txt = str(msg)
          print(txt)
          return 1
  
      if (test_read, test_write) == (None, None):
          test_read = test_write = True
  
      m = Measure(n, test_read, test_write)
      m.measure_all()
      m.print_report()
  
      return 0
docs: Main function to run benchmarks.
      @param  argv:   command-line arguments.
      @return:        exit code (0 is OK).