rqt_joint_trajectory controller : Import Error: no module named rospkg.rospack

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Good morning,

I installed the package with:

sudo apt install ros-noetic-rqt-joint-trajectory-controller

but when running

rosrun rqt_joint_trajectory_controller rqt_joint_trajectory_controller

I got this error

Traceback (most recent call last):  
File "/opt/ros/noetic/lib/rqt_joint_trajectory_controller/rqt_joint_trajectory_controller", line 5, in <module>
    from rqt_gui.main import Main
File "/opt/ros/noetic/lib/python3/dist-packages/rqt_gui/main.py", line 40, in <module>
    from rospkg.rospack import RosPack
ImportError: No module named rospkg.rospack

How to solve this?