To be fair, there are no macros in that example. Just good ol polymorphism and exceptionaly hackable semantics.

Pycall does rely on macros and so do essentially all the other interop packages.

Sure, they all provide nice macro interfaces, but nothing in the above example required those macros as far as I understand.

This is not to say macros aren't awesome.

I'm pretty sure that macros are involved in the invocation of the python function.