I’ve managed to find a workaround, and included all of the changes I’d implemented below which are different than the course sections:
Creating the initial package (in ~/catkin_ws/src): Need to include “rospy”, “std_msgs”, and “message_generation” for dependencies.
catkin_create_pkg <package_name> rospy std_msgs message_generation
CMakeLists.txt
INCLUDE rospy in find_package of CMakeLists.txt as below
find_package(catkin REQUIRED COMPONENTS
rospy
std_msgs
message_generation
)
package.xml
EXCLUDE this line (commented out in my version)
<build_export_depend>message_runtime</build_export_depend>
Once all is updated use these commands to delete and reset the /build and /devel folders using:
cd ~/catkin_ws
rm -rf build/ devel/
catkin_make
source devel/setup.bash
When in ~/catkin_ws directory:
roslaunch exercise_33 publish_age.launch
This starts the topic, then need to ‘echo’ the topic value in another terminal.
Other sources:
https://get-help.robotigniteacademy.com/t/no-module-named-actions-quiz-ros-basics-python/25205/8
