code: def option(*param_decls, **attrs):
      
      def decorator(f):
          if 'help' in attrs:
              attrs['help'] = inspect.cleandoc(attrs['help'])
          OptionClass = attrs.pop('cls', Option)
          _param_memo(f, OptionClass(param_decls, **attrs))
          return f
      return decorator
docs: Attaches an option to the command.  All positional arguments are
      passed as parameter declarations to :class:`Option`; all keyword
      arguments are forwarded unchanged (except ``cls``).
      This is equivalent to creating an :class:`Option` instance manually
      and attaching it to the :attr:`Command.params` list.
  
      :param cls: the option class to instantiate.  This defaults to
                  :class:`Option`.