Ubuntu 20.04 and ROS Noetic -> ImportError: No module named rospkg

[Helge543]

Hi, I'm working on Ubuntu 20.04 and ROS Noetic. I want to install this tello driver but I get the following error message:

SUMMARY
========

PARAMETERS
 * /rosdistro: noetic
 * /rosversion: 1.15.11
 * /tello/tello_driver_node/camera_calibration: /home/user...
 * /tello/tello_driver_node/connect_timeout_sec: 10.0
 * /tello/tello_driver_node/local_cmd_client_port: 8890
 * /tello/tello_driver_node/local_vid_server_port: 6038
 * /tello/tello_driver_node/stream_h264_video: True
 * /tello/tello_driver_node/tello_cmd_server_port: 8889
 * /tello/tello_driver_node/tello_ip: 192.168.10.1

NODES
  /tello/
    image_compressed (image_transport/republish)
    tello_driver_node (tello_driver/tello_driver_node)

auto-starting new master
process[master]: started with pid [35315]
ROS_MASTER_URI=http://localhost:11311

setting /run_id to b96e7966-fc1d-11eb-befe-89052bf0da48
process[rosout-1]: started with pid [35325]
started core service [/rosout]
process[tello/tello_driver_node-2]: started with pid [35332]
process[tello/image_compressed-3]: started with pid [35333]
Traceback (most recent call last):
  File "/home/user/catkin_ws/src/tello_driver/nodes/tello_driver_node", line 2, in <module>
    import rospy
  File "/opt/ros/noetic/lib/python3/dist-packages/rospy/__init__.py", line 49, in <module>
    from .client import spin, myargv, init_node, \
  File "/opt/ros/noetic/lib/python3/dist-packages/rospy/client.py", line 52, in <module>
    import roslib
  File "/opt/ros/noetic/lib/python3/dist-packages/roslib/__init__.py", line 50, in <module>
    from roslib.launcher import load_manifest  # noqa: F401
  File "/opt/ros/noetic/lib/python3/dist-packages/roslib/launcher.py", line 42, in <module>
    import rospkg
ImportError: No module named rospkg
[tello/tello_driver_node-2] process has died [pid 35332, exit code 1, cmd /home/user/catkin_ws/src/tello_driver/nodes/tello_driver_node __name:=tello_driver_node __log:=/home/user/.ros/log/b96e7966-fc1d-11eb-befe-89052bf0da48/tello-tello_driver_node-2.log].
log file: /home/user/.ros/log/b96e7966-fc1d-11eb-befe-89052bf0da48/tello-tello_driver_node-2*.log

I've seen that ImportError: No module named rospkg is pretty well known and I've been reading through a lot of posts but most of the people either have problems with conda (which does not run on my machine) or with the python version (they changed the version from 2. to 3.). My python version is 3.8.10 so I don't think that there is the problem. Does anyone know what the problem could be? Help would be much appreciated.

[cottsay]

The most common reason I've seen missing system modules like this results from the use of a non-default Python interpreter. From what I can tell, you installed ros-noetic-roslib (and likely other dependencies of tello) via apt, which would have installed the python3-rospkg-modules deb on your system.

Please run which python3 to determine where your interpreter lives. If it doesn't live at /usr/bin/python3, then you have two choices:

1. Start using the system default interpreter instead, which should have no problems finding the system-installed Python packages.
2. Install ALL of the ROS Python dependencies via pip using your non-standard interpreter. This will likely be an uphill battle.

If my hunch is incorrect and you are indeed using the system interpreter, then we'll need to dig deeper. Please run the following and let me know what you find:
python3 -c "from distutils.sysconfig import get_python_lib; print(get_python_lib())"

[VincentDuf]

Hi !
I'm facing the same issue with a ROS/Gazebo simulator.
I have a colleague trying to put the simulator on his Ubuntu20.04 machine but impossible to find python-rospkg and python-rospy packages, is it normal ?

FIY we spent a lot of time checking the repo sources, environment setup etc.. Couldn't find anything different from Ubuntu18.04 on which the simulator runs well.

It seems that this issue is related to Ubuntu 20.04 depreciating python2, is that correct ? is there a way around this ?

Thanks !

[O2KAN]

Hey, if you are using anaconda, try the same launch file after deactivating anaconda using: conda deactivate

[nuclearsandwich]

I have a colleague trying to put the simulator on his Ubuntu20.04 machine but impossible to find python-rospkg and python-rospy packages, is it normal ?

Ubuntu 20.04 has dropped support for many python2 packages in favor of their python3 counterparts. Please do not use old issues to ask new questions. You can ask questions on https://answers.ros.org or if you believe that you've found a bug in rospkg you can report it with a new issue.

[Miha22]

This is an issue because Ubuntu 20.04 has dropped python and python2, and now using python 3. Install the following lib to run ROS on Ubuntu 20.04: sudo apt install python-is-python3

[Miha22]

I have a colleague trying to put the simulator on his Ubuntu20.04 machine but impossible to find python-rospkg and python-rospy packages, is it normal ?

Ubuntu 20.04 has dropped support for many python2 packages in favor of their python3 counterparts. Please do not use old issues to ask new questions. You can ask questions on https://answers.ros.org or if you believe that you've found a bug in rospkg you can report it with a new issue.

Yes, you are correct.

[nuclearsandwich]

This is an issue because Ubuntu 20.04 has dropped python and python2, and now using python 3. Install the following lib to run ROS on Ubuntu 20.04: sudo apt install python-is-python3

I don't recommend installing this when running ROS as it could interfere with scripts that expect /usr/bin/python to be python 2 and will not run correctly.

If you encounter difficulties setting up ROS please ask for help on https://answers.ros.org

To avoid this issue becoming a honeypot for future questions I am going to close it (the original author never followed up) and lock it.