code: def result(self, timeout=None):
          
          self._clear_tb_log()
          if self._result is not None:
              return self._result
          if self._exc_info is not None:
              try:
                  raise_exc_info(self._exc_info)
              finally:
                  self = None
          self._check_done()
          return self._result
docs: If the operation succeeded, return its result.  If it failed,
          re-raise its exception.
  
          This method takes a ``timeout`` argument for compatibility with
          `concurrent.futures.Future` but it is an error to call it
          before the `Future` is done, so the ``timeout`` is never used.