code: def verify_ed25519_signature_cmdln(args=None, exception=SystemExit):
      
      args = args or sys.argv[1:]
      parser = argparse.ArgumentParser(
          description="""Verify an ed25519 signature from the command line.
  
  Given a file and its detached signature, verify that it has been signed with
  a valid key. This key can be specified on the command line; otherwise we'll
  default to ``config['ed25519_public_keys']``.""")
      parser.add_argument('--pubkey', help='path to a base64-encoded ed25519 pubkey, optional')
      parser.add_argument('file_path')
      parser.add_argument('sig_path')
      opts = parser.parse_args(args)
      log = logging.getLogger('scriptworker')
      log.setLevel(logging.DEBUG)
      logging.basicConfig()
      pubkeys = {}
      if opts.pubkey:
          pubkeys['cmdln'] = [read_from_file(opts.pubkey)]
      pubkeys.update(dict(DEFAULT_CONFIG['ed25519_public_keys']))
      contents = read_from_file(opts.file_path, file_type='binary')
      signature = read_from_file(opts.sig_path, file_type='binary')
      for key_type, seeds in pubkeys.items():
          for seed in seeds:
              try:
                  verify_ed25519_signature(
                      ed25519_public_key_from_string(seed), contents, signature,
                      "didn't work with {}".format(seed)
                  )
                  log.info("Verified good with {} seed {} !".format(
                      key_type, seed
                  ))
                  sys.exit(0)
              except ScriptWorkerEd25519Error:
                  pass
      raise exception("This is not a valid signature!")
docs: Verify an ed25519 signature from the command line.
  
      Args:
          args (list, optional): the commandline args to parse. If ``None``, use
              ``sys.argv[1:]``. Defaults to ``None``.
          exception (Exception, optional): the exception to raise on failure.
              Defaults to ``SystemExit``.