def future_done(self, future, rv):
        if rv != 0:
            logging.error("error: async operation: %s on sink: %s" %
                          (rv, self))
        if future:
            future.done_rv = rv
            future.done.set()


# --------------------------------------------------
Draw a line to mark a single observation.
dataset/ETHPy150Open membase/membase-cli/pump.py/Sink.future_done--crossover with--dataset/ETHPy150Open mwaskom/seaborn/seaborn/categorical.py/_ViolinPlotter.draw_single_observation