models.py 文件源码

def __deepcopy__(self, memo):
        """
        Hack sorting double chained task lists by task_id to avoid hitting
        max_depth on deepcopy operations.
        """
        sys.setrecursionlimit(5000)  # TODO fix this in a better way
        cls = self.__class__
        result = cls.__new__(cls)
        memo[id(self)] = result

        for k, v in list(self.__dict__.items()):
            if k not in ('user_defined_macros', 'user_defined_filters', 'params'):
                setattr(result, k, copy.deepcopy(v, memo))
        result.params = self.params
        if hasattr(self, 'user_defined_macros'):
            result.user_defined_macros = self.user_defined_macros
        if hasattr(self, 'user_defined_filters'):
            result.user_defined_filters = self.user_defined_filters
        return result