Issue: Getting it working
Key skill: problem decomposition

So, here's my version of the list:

1. Our typing of the shell script name.
2. The python script that is run.
3. The shell script itself.
4. The Python interpreter.
5. The shell itself.

I've put these in the rough order of ease of testing and potential complication of issues – there's no point in trying to work out if there's an issue with the shell, if the problem is us mis-typing the shell script name.

Assuming you've typed the name of the shell script correctly (adding the file extension if necessary), let's think about the next one: the Python script. By running the Python script with a shell script, we should be making it easier for users, but we've added another layer of complication. How might we remove that to check the Python file is ok? (Don't overthink it!)

1. Start
2. The problem
3. Decomposing the problem
4. Testing the parts <-- next
5. Solving the issues 1
6. Solving the issues 2
7. Final points