_default_manager is the same as objects on most of our models. But
when a model class is stored in a variable, the type system doesn’t
know which model the variable is referring to, so it can’t know that
objects even exists (Django doesn’t add it if the user added a custom
manager of a different name). django-stubs used to incorrectly assume
it exists unconditionally, but it no longer does.
Signed-off-by: Anders Kaseorg <anders@zulip.com>
This is necessary for the migration 0386_fix_attachment_caches to run,
and likely makes more convenient any future parallel code interacting
with both Attachment and ArchivedAttachment.
This migration needs to be run after the previous commit is deployed
to a given Zulip installation, to fix any stale values of
is_realm_public and is_web_public.
Tim Abbott
Anders Kaseorg
Zixuan James Li
Zixuan James Li