Many bots not being detected as bots

[fluffy-critter]

The user-agent string Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/17.4 Safari/605.1.15 (Applebot/0.1; +http://www.apple.com/go/applebot) fits all standards for bot declaration, but is not being detected as a bot:

>>> ua=user_agents.parse('Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/17.4 Safari/605.1.15 (Applebot/0.1; +http://www.apple.com/go/applebot)')
>>> ua.is_bot
False

Is there some reason why this library isn't using the presence of r'\+https?://' as a bot/spider indicator?