docs: def docopt(doc, argv=None, help=True, version=None, options_first=False):
      """Parse `argv` based on command-line interface described in `doc`.
  
      `docopt` creates your command-line interface based on its
      description that you pass as `doc`. Such description can contain
      --options, <positional-argument>, commands, which could be
      [optional], (required), (mutually | exclusive) or repeated...
  
      Parameters
      ----------
      doc : str
          Description of your command-line interface.
      argv : list of str, optional
          Argument vector to be parsed. sys.argv[1:] is used if not
          provided.
      help : bool (default: True)
          Set to False to disable automatic help on -h or --help
          options.
      version : any object
          If passed, the object will be printed if --version is in
          `argv`.
      options_first : bool (default: False)
          Set to True to require options preceed positional arguments,
          i.e. to forbid options and positional arguments intermix.
  
      Returns
      -------
      args : dict
          A dictionary, where keys are names of command-line elements
          such as e.g. "--verbose" and "<path>", and values are the
          parsed values of those elements.
  
      Example
      -------
      >>> from docopt import docopt
      >>> doc = '''
      Usage:
          my_program tcp <host> <port> [--timeout=<seconds>]
          my_program serial <port> [--baud=<n>] [--timeout=<seconds>]
          my_program (-h | --help | --version)
  
      Options:
          -h, --help  Show this screen and exit.
          --baud=<n>  Baudrate [default: 9600]
      '''
      >>> argv = ['tcp', '127.0.0.1', '80', '--timeout', '30']
      >>> docopt(doc, argv)
      {'--baud': '9600',
       '--help': False,
       '--timeout': '30',
       '--version': False,
       '<host>': '127.0.0.1',
       '<port>': '80',
       'serial': False,
       'tcp': True}
  
      See also
      --------
      * For video introduction see http://docopt.org
      * Full documentation is available in README.rst as well as online
        at https://github.com/docopt/docopt#readme
  
      """
      if argv is None:
          argv = sys.argv[1:]
      DocoptExit.usage = printable_usage(doc)
      options = parse_defaults(doc)
      pattern = parse_pattern(formal_usage(DocoptExit.usage), options)
      # [default] syntax for argument is disabled
      #for a in pattern.flat(Argument):
      #    same_name = [d for d in arguments if d.name == a.name]
      #    if same_name:
      #        a.value = same_name[0].value
  
      argv = parse_argv(TokenStream(argv, DocoptExit), list(options),
                        options_first)
      pattern_options = set(pattern.flat(Option))
      for ao in pattern.flat(AnyOptions):
          doc_options = parse_defaults(doc)
          ao.children = list(set(doc_options) - pattern_options)
          #if any_options:
          #    ao.children += [Option(o.short, o.long, o.argcount)
          #                    for o in argv if type(o) is Option]
      extras(help, version, argv, doc)
      matched, left, collected = pattern.fix().match(argv)
      if matched:
          return Dict((a.name, a.value) for a in (pattern.flat() + collected))
      raise DocoptExit()