If using astropy v4.2 or higher you get a deprecation warning about importing the astropy._erfa library as erfa is now a separate package (pyerfa), which is a requirement of astropy.
This PR bumps the required version of astropy for libstempo to be at least 4.2 and also imports erfa directly, thus getting rid of the deprecation warning.
If using astropy v4.2 or higher you get a deprecation warning about importing the astropy._erfa library as erfa is now a separate package (pyerfa), which is a requirement of astropy.
This PR bumps the required version of astropy for libstempo to be at least 4.2 and also imports erfa directly, thus getting rid of the deprecation warning.