Port pipe_drivers to Python 3
Port obs_test to Python 3 and modernize unit tests
Port pipe_base to Python 3
Adapt daf_butlerUtils to py3
Upgrade mpi4py to latest upstream
Fix octal umask handling in ctrl_pool
Fix failure to fail
Add unit tests for ctrl_pool
fred3m changed the blocking relationship to a relates relationship between this ticket and DM-5748. I realise this is an overly pedantic discussion...
My mistake, I changed the wrong ticket today.
Using openmpi on OS X the ctrl_pool demo is able to run using n=1,3,5 in both python 2 and 3. There are currently no tests for ctrl_pool, so Jenkins can only verify that it builds correctly (see DM-3845).
Looks ok. Some comments on the PR. I think this may be the first python3 port involving super.
Rebased with master and tested the demo locally (py2 and py3) and built on Jenkins.