James Mullaney reported the following bug on confluence:
We're using the astrometry.net extension to perform astrometry. In v15 and v16 of the stack, I've noticed that meas_extensions_astrometryNet/python/lsst/meas/extensions/astrometryNet/anetAstrometry.py refers to self.distortionContext (see here). However, it seems that the distortionContext function was removed on the 4th of November, 2017 by this commit. I may be mistaken, but this seems to be a bug introduced by not catching all references to distortionContext when making that commit.