How did you find it? Did you happen to notice it when you saw the imports?
It's usually pops up in issues with efforts to break modules cycles
I'm not quite sure how it is critical right now, but there was a discussion that cycles in modules slow down ~guix pull~.
Let's comment astropy out with some notes about optional test dependency and potential module cycle.
Looking forward for v2, patches look good.
If you have wider plan of upcoming patches please share to coordinate efforts ;-).
Regards,
Oleg