fix Python >= 3.10 compatibility
Support for importing MutableSet from collections instead of collections.abc was deprecated in 3.3, with a warning added in 3.7, and removed in 3.10.
Due to an influx of spam, we have had to temporarily disable account registrations. Please write an email to accountsupport@archlinux.org, with your desired username, if you want to get access. Sorry for the inconvenience.
Support for importing MutableSet from collections instead of collections.abc was deprecated in 3.3, with a warning added in 3.7, and removed in 3.10.