Figure out macos wheels

[spxiwh]

Let's also try and see why macos wheels don't work ...

[codecov-commenter]

Codecov Report

Merging #21 (71cafc5) into master (d5b2cda) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master      #21   +/-   ##
=======================================
  Coverage   20.94%   20.94%           
=======================================
  Files          11       11           
  Lines        1318     1318           
=======================================
  Hits          276      276           
  Misses       1042     1042           

Flag	Coverage Δ
Linux	20.94% <ø> (ø)
macOS	23.21% <ø> (ø)
python3.6	19.97% <ø> (ø)
python3.7	19.97% <ø> (ø)
python3.8	20.99% <ø> (ø)
python3.9	20.99% <ø> (ø)

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[spxiwh]

I've spent some time trying to debug this one, but I've no idea why this won't "repair" the wheel after building it successfully. I think there's something weird going on with building the mac wheels, which might leave the installed code broken, but I've not managed to identify what it is. I'm going to leave this for now, if anyone wants a macos wheel, they'll have to figure this out!