Black 23 enforces some slightly more specific rules about empty line
counts and redundant parenthesis removal, but the result is still
compatible with Black 22.
(This does not actually upgrade our Python environment to Black 23
yet.)
Signed-off-by: Anders Kaseorg <anders@zulip.com>
Generated by `pyupgrade --py3-plus --keep-percent-format` on all our
Python code except `zthumbor` and `zulip-ec2-configure-interfaces`,
followed by manual indentation fixes.
Signed-off-by: Anders Kaseorg <anders@zulipchat.com>
Also adds Confirmation.type, and cleans up the rest of Confirmation to look
more like the model definitions in zerver.
In the migration, all existing confirmations adopt the type
USER_REGISTRATION, to be conservative. In a few commits, different
confirmation types will have different validity periods, and
USER_REGISTRATION will have the shortest default.