Task error?

[LemonQC]

I run task builder and run any task py Traceback (most recent call last): File "task_builder.py", line 134, in new_variation descriptions = self.scene.init_episode( File "/home/lemon/RLBench-master/tools/../rlbench/backend/scene.py", line 136, in init_episode self.task.validate() File "/home/lemon/RLBench-master/tools/../rlbench/backend/task.py", line 274, in validate self._waypoints = self._get_waypoints() File "/home/lemon/RLBench-master/tools/../rlbench/backend/task.py", line 415, in _get_waypoints feasible, way_i = self._feasible(waypoints) File "/home/lemon/RLBench-master/tools/../rlbench/backend/task.py", line 366, in _feasible path.set_to_end() AttributeError: 'tuple' object has no attribute 'set_to_end'