@property
    def error(self):
        # Copy the error from any failed item to be the error for the whole
        # barrier. The first error seen "wins". Also handles the case where
        # the WorkItems passed into the barrier have already completed and
        # been marked with errors.
        for item in self:
            if isinstance(item, WorkItem) and item.error:
                return item.error
        return None
Returns the error for this barrier and all work items, if any.
dataset/ETHPy150Open bslatkin/dpxdt/dpxdt/client/workers.py/ResultList.error