Solving the venv headache with a small utility?

Python’s virtual environments (venvs) are great — until you actually try to use them. Every project has its own .venv, but the moment you move around your filesystem, you’re stuck manually running: source .venv/bin/activate …over and over, in every project, forever. You have to activate the venv in every shell where you are. WHY? The flaw is structural: using environment variables for activating the venv was a design error. The reason is that it's impossible for a program to modify the shell env