While going through the sequence of instructions to install ROS on my local machine, I encountered a couple of errors which I was able to get around.
First was in the “Initialize rosdep” step. Upon entering the sudo rosdep init command, I got the error: sudo: rosdep: command not found. I installed rosdep with the command sudo pip install -U rosdep
The second error was in the command to install dependencies for building packages. I had to append ‘3’ to all the occurences of python.
sudo apt-get install python3-rosinstall python3-rosinstall-generator python3-wstool build-essential
My installation is on a Rapberry Pi 4. The OS is Ubuntu 20.04 LTS server with lubuntu desktop.