I don't want to knock anyone's project but I fail to see the way in which this resembles back-of-the-envelope calculations (which I take to mean, roughly, estimates RE order of magnitude). This seems more like plain old arithmetic with some built-in units. Am I missing something?
That’s a creative use of a custom <i>2to3</i> fixer [1] to transform the calculations [2]. Too bad this will no longer work with the removal of <i>2to3</i> in Python 3.13.<p>[1]: <a href="https://docs.python.org/3/library/2to3.html#fixers" rel="nofollow">https://docs.python.org/3/library/2to3.html#fixers</a><p>[2]: <a href="https://github.com/rescrv/napkin/blob/e6a4de2/napkin/substitute.py">https://github.com/rescrv/napkin/blob/e6a4de2/napkin/substit...</a>