Use type(None) rather than bool to define knobs which are represented as
command line flags. This allows declaring both "--option" and
"--option={0,1}"-style command line options.
Use enum.Enum subclasses instead of set literals to declare enumerations.
Use typing.List[T] instead of (list, T) to declare lists. (Note that a
minimal reimplementation of typing.List is used instead of the Python 2
backport of the typing module due to non-technical reasons.)
Use CheckedIPAddress instead of 'ip' and 'ip-local' to declare IP
addresses.
https://fedorahosted.org/freeipa/ticket/6392
Reviewed-By: Martin Basti <mbasti@redhat.com>
Stanislav Levin
Jan Cholasta