Hello Python 3.9, goodbye Python 3.5!
Fix algorithm for generating output names when output names clash (#1342) by @pvanheus
allow pytest version 6 and other build cleanups (#1345) by @mr-c
Drop support/testing/CI for Python 3.5 (#1346) by @mr-c
Python 3.9 testing (#1352) by @mr-c
- upgrade to mypy 0.790
Singularity: Support both --userns error messages (#1350) by @jonathanxu18
(also removes --pid when using --userns with Signularity, for better Singularity in Kubernetes support)