[$] Positional-only parameters for Python

Arguments can be passed to Python functions by position or bykeyword-generally both. There are times when API designers may wish torestrict some function parameters to only be passed by position, which isharder than some think it should be in pure Python. That has led to a PEPthat is meant to make the situation better, but opponents say it doesn't really do that;it simply replaces one obscure mechanism with another. The PEP wasassigned a fairly well-known "BDFL delegate" (former BDFL Guido van Rossum), who hasaccepted it, presumably for Python 3.8.