docs: def unwrap_or_else(self, op: Callable[[E], U]) -> Union[T, U]:
          """
          Returns the sucess value in the :class:`Result` or computes a default
          from the error value.
  
          Args:
              op: The function to computes default with.
  
          Returns:
              The success value in the :class:`Result` if it is
               a :meth:`Result.Ok` value, otherwise ``op(E)``.
  
          Examples:
              >>> Ok(1).unwrap_or_else(lambda e: e * 10)
              1
              >>> Err(1).unwrap_or_else(lambda e: e * 10)
              10
          """
          return cast(T, self._val) if self._is_ok else op(cast(E, self._val))