docs: def ok(self) -> Option[T]:
          """
          Converts from :class:`Result` [T, E] to :class:`option.option_.Option` [T].
  
          Returns:
              :class:`Option` containing the success value if `self` is
              :meth:`Result.Ok`, otherwise :data:`option.option_.NONE`.
  
          Examples:
              >>> Ok(1).ok()
              Some(1)
              >>> Err(1).ok()
              NONE
          """
          return Option.Some(cast(T, self._val)) if self._is_ok else cast(Option[T], NONE)