docs: def main(cls, args=None):
          """
          Fill in command-line arguments from argv
          """
          if args is None:
              args = sys.argv[1:]
  
          try:
              o = cls()
              o.parseOptions(args)
          except usage.UsageError as e:
              print(o.getSynopsis())
              print(o.getUsage())
              print(str(e))
              return 1
          except CLIError as ce:
              print(str(ce))
              return ce.returnCode
  
          return 0