new ASE version uses f-strings but is installed under python 3.5

[ltalirz]

See CI failure https://github.com/aiidateam/aiida-core/runs/965898145?check_suite_focus=true#step:11:334

It looks like this is an issue of ASE itself - README says python3.6 or later, but pypi metadata includes 3.5.

[ltalirz]

Opened issue https://gitlab.com/ase/ase/-/issues/718

[greschd]

As far as I understand, the PyPI metadata (Trove classifiers) aren't taken into account when choosing which version to install at all. The correct way to declare this incompatibility would be a python_requires in setup.py - which ASE doesn't seem to be doing at all, see https://gitlab.com/ase/ase/-/blob/master/setup.py

Crucially, the python_requires needs to be set already one version before the compatibility is dropped - i.e., only if there is a released version with python_requires>=3.5 will it install that if the newest version has >=3.6.

[ltalirz]

Thanks @greschd , linked in the issue!

[csadorf]

The issue is resolved by recent ase patch releases.