Rémy-Christophe Schermesser

This is a very draft PR to answer this [need](https://github.com/tarpas/pytest-testmon/issues/77). I had a hard time understanding how `testmon` works internally, and also how to test this. I'll happily get any...

## Summary I'm trying to use deadcode on our code base, and it crashes. I managed to reduce the error to a few lines, and find the cultprit: ``` @Class().function()...