Optional[List] is clunky; an empty sequence can more elegantly convey
"no variants". By downgrading "List" to "Sequence", we can also accept
tuples; this is useful for the empty tuple specifically, which we may
use as a default parameter because it is immutable.
Signed-off-by: John Snow <jsnow@redhat.com>
Message-Id: <20210216021809.134886-18-jsnow@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
[Doc string touched up]
Reviewed-by: Markus Armbruster <armbru@redhat.com>