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>
By adding some additional plumbing (through PreregistrationUser) of the
full_name and an additional full_name_validated option, we
pre-populate the Full Name field in the registration form when coming
through a social backend (google/github/saml/etc.) and potentially skip
the registration form (if the user would have nothing to do there other
than clicking the Confirm button) and just create the account and log
the user in.