Why is this library forcing kerberos attempts?

See: https://opendev.org/jjb/python-jenkins/src/branch/master/jenkins/__init__.py#L69

try:
    import requests_kerberos
except ImportError:
    requests_kerberos = None

This results in an "ERROR", but not really and error...

2019-10-22 09:12:34,983 - ERROR - handle_other(): Mutual authentication unavailable on 403 response

As the below code jams in that option to try:

        if requests_kerberos is not None:
            self._auths.append(
                ('kerberos', requests_kerberos.HTTPKerberosAuth())
            )

Why? This should absolutely be an argument/toggle or a capture of the requests 403 message to output it as "Trying kerberos, skipping due to X" of some sort.