AttributeError: 'rrt_demo' object has no attribute 'Parent'

[KuKuKI233]

Hi,
When I run the rrt3D.py, it occured a mistake:
Original exception was: Traceback (most recent call last): File "/home/xia/mydemo01_ws/src/PathPlanning-master/Sampling_based_Planning/rrt_3D/utils3D.py", line 410, in <module> A.run() File "/home/xia/mydemo01_ws/src/PathPlanning-master/Sampling_based_Planning/rrt_3D/utils3D.py", line 403, in run visualization(self) File "/home/xia/mydemo01_ws/src/PathPlanning-master/Sampling_based_Planning/rrt_3D/../../Sampling_based_Planning/rrt_3D/plot_util3D.py", line 96, in visualization for i in initparams.Parent: AttributeError: 'rrt_demo' object has no attribute 'Parent'
What should I do next?