There is no age_info topic in exercise 4.3

Course Support ROS Basics In 5 Days (Python)
7

For this kind of error, it could mean two things. Please try them in this order:

  1. You have properly built and sourced the module on one web shell, but it is not working on another web shell.
  • You need to source ~/catkin_ws/devel/setup.bash on the shell where you are running the program
  1. You have not properly built and sourced the package:
    # On web shell 1
cd ~/catkin_ws
rm -rf build/ devel/
catkin_make
source devel/setup.bash

# On any other web shell
cd ~/catkin_ws
source devel/setup.bash
1 Like