code: def compile(cfg_path, out_path, executable=None, env=None, log=None):
      
      try:
          check_call(
              [(executable or 'ace'), '-g', cfg_path, '-G', out_path],
              stdout=log, stderr=log, close_fds=True,
              env=(env or os.environ)
          )
      except (CalledProcessError, OSError):
          logging.error(
              'Failed to compile grammar with ACE. See {}'
              .format(log.name if log is not None else '<stderr>')
          )
          raise
docs: Use ACE to compile a grammar.
  
      Args:
          cfg_path (str): the path to the ACE config file
          out_path (str): the path where the compiled grammar will be
              written
          executable (str, optional): the path to the ACE binary; if
              `None`, the `ace` command will be used
          env (dict, optional): environment variables to pass to the ACE
              subprocess
          log (file, optional): if given, the file, opened for writing,
              or stream to write ACE's stdout and stderr compile messages