I've added Breaks to the package in git: aws-shell (<= 0.2.1) [1] mycli (<< 1.19) pgcli (<< 2) python3-ipython (<< 7) python3-jupyter-console (<< 6) python3-softlayer (<< 5.8)
[1] No upstream version which fixes this, but I assume adding an unversioned Breaks: is a bad idea. I think that having heard from sagemath, pgcli and mycli, the only outstanding blockers are aws-shell (#944542) and possibly mlbstreamer (#944545). For my part (ipython, jupyter-console) I'm waiting for python-backcall and ipython-py2 to go through NEW before ipython can be upgraded.