This may also go into erfa itself, but it should be possible to simplify the generation of the python interface to erfa, possibly doing away with the large template, and possibly auto-generating the files on the fly (thus reducing the memory load and speeding up initialization for those who do not use Time and SkyCoord enough to care about erfa).

These ideas were partially implemented in #3181, but that project got stalled. This is a reminder to think about this...