It seems that `os.sched_getaffinity`called in the enclosed link is not supported by OSX. Or at least it doesn't work on my laptop. I am running Python 3.8.8 https://github.com/abacusorg/abacusutils/blob/16d97281c4c769f0188a5b2753e46d0bd2a0ed67/abacusnbody/data/compaso_halo_catalog.py#L296