v3.6.0
I apologize for the 3.6.0 release coming so shortly after the 3.5.0 release; it is fuelled by demands from the calendaring-sync and calendaring projects. If you're doing packaging or maintaining dependencies and find bumping the version costly, then wait two weeks - maybe there will be a 3.7.0 release.
The configuration file is now read through the new calendaring-config package, shared with plann, so the two read the same file the same way - with new features like password_command, keyring lookups and per-key environment overrides. save(no_overwrite=True) and save(no_create=True) now leave the check to the server through wildcard preconditions (If-None-Match: *, If-Match: *), closing a race with other clients. Calendar objects keep the raw data as the server sent it (raw_data), and a single occurrence can be cancelled with cancel(). More server profiles have been checked and updated.
Also released without the niquests dependency as 3.6.0a0 - install requests (for the sync client) and/or httpx2 (for the async client) alongside it.