Toward python39

[hippo91]

Steps

• Write a good description on what the PR does.

Description

This PR is an attempt to deal with python 3.9. The functional tests that where failing are now successful thanks to pylint-dev/astroid#858. The star_needs_assignment_py35 is, IMHO, useless for python3.9, because potential problem with star operator is now detected in the new parser used by python3.9. (with previous version it was detected only at compile time).

Related Issue

Closes #3895 #3876

[Pierre-Sassoulas]

Maybe not the right place to discuss this, but shouldn't we also drop python 3.5 ? It has ceased to be supported since September 2020.

[dbaty]

Maybe not the right place to discuss this, but shouldn't we also drop python 3.5 ? It has ceased to be supported since September 2020.

Yes, this was briefly discussed in another issue. I said I would tackle it but did not. I can probably look at it in a week or two, if nobody beats me to it. :) Anyway, we can discuss that in this specifically created new issue: #3965.

[PCManticore]

Other than relaxing the astroid version so the CI is green, this looks good to go.

[coveralls]

Coverage increased (+0.008%) to 90.862% when pulling bacbf62 on hippo91:toward_python39 into 17325f2 on PyCQA:master.

[coveralls]

Coverage increased (+0.008%) to 90.862% when pulling bacbf62 on hippo91:toward_python39 into 17325f2 on PyCQA:master.

[JulienPalard]

Thanks for all the work here ♥