This is a super cool idea, I'm surprised there isn't ambiguity in parsing shell commands vs python.

For example if a user types "a | b", do they want to run process a and pipe it into b, or are they trying to bitwise or variables a and b?

There's a Python mode and a subprocess mode.

https://xon.sh/tutorial.html#python-mode-vs-subprocess-mode

There is ambiguity. "open .file" is parsed as "open.file", which is an error in Python