moveit2 demo question

edit

I try to run plan.py so I create a work_space like this.

plan.py needs moveit_commander so put it in work_space too.

Then I run command : colcon build --symlink-instal & source install/setup.bash and start up lanuch file by command : ros2 launch moveit2_commander demo.launch.py

the error show below

chaos@chaos4ros2:~/moveit2_ws/src/moveit2_tutorials/doc/moveit2_commander_ws$ ros2 launch moveit2_commander demo.launch.py
[INFO] [launch]: All log files can be found below /home/chaos/.ros/log/2021-04-23-09-18-42-465832-chaos4ros2-14300
[INFO] [launch]: Default logging verbosity is set to INFO
[INFO] [plan-1]: process started with pid [14302]
[plan-1] Traceback (most recent call last):
[plan-1]   File "/home/chaos/moveit2_ws/src/moveit2_tutorials/doc/moveit2_commander_ws/install/moveit2_commander/lib/moveit2_commander/plan", line 11, in <module>
[plan-1]     load_entry_point('moveit2-commander', 'console_scripts', 'plan')()
[plan-1]   File "/usr/lib/python3/dist-packages/pkg_resources/__init__.py", line 490, in load_entry_point
[plan-1]     return get_distribution(dist).load_entry_point(group, name)
[plan-1]   File "/usr/lib/python3/dist-packages/pkg_resources/__init__.py", line 2854, in load_entry_point
[plan-1]     return ep.load()
[plan-1]   File "/usr/lib/python3/dist-packages/pkg_resources/__init__.py", line 2445, in load
[plan-1]     return self.resolve()
[plan-1]   File "/usr/lib/python3/dist-packages/pkg_resources/__init__.py", line 2451, in resolve
[plan-1]     module = __import__(self.module_name, fromlist=['__name__'], level=0)
[plan-1]   File "/home/chaos/moveit2_ws/src/moveit2_tutorials/doc/moveit2_commander_ws/build/moveit2_commander/moveit2_commander/plan.py", line 11, in <module>
[plan-1]     from moveit_commander import RobotCommander, roscpp_initialize, roscpp_shutdown
[plan-1]   File "/home/chaos/moveit2_ws/src/moveit2_tutorials/doc/moveit2_commander_ws/build/moveit_commander/moveit_commander/__init__.py", line 2, in <module>
[plan-1]     from .roscpp_initializer import *
[plan-1]   File "/home/chaos/moveit2_ws/src/moveit2_tutorials/doc/moveit2_commander_ws/build/moveit_commander/moveit_commander/roscpp_initializer.py", line 35, in <module>
[plan-1]     from moveit_ros_planning_interface import _moveit_roscpp_initializer
[plan-1] ModuleNotFoundError: No module named 'moveit_ros_planning_interface'
[ERROR] [plan-1]: process has died [pid 14302, exit code 1, cmd '/home/chaos/moveit2_ws/src/moveit2_tutorials/doc/moveit2_commander_ws/install/moveit2_commander/lib/moveit2_commander/plan --ros-args -r __node:=plan'].

I installed moveit2 correctly、and 「moveit_ros_planning_interface」is included in the pkg list（confirm it by ros2 pkg list）

I'm not familiar with build system. What else do I have to do?