[networked]

I'm not familiar enough with YAML to see the problem at a glance but parsing the snippet with an online parser [1] suggests that unless you put quotation marks around "NO" it gets parsed into a boolean False. Looks precarious, especially since not requiring strings to be quoted is kind of a selling point of YAML.

[1] https://yaml-online-parser.appspot.com/

[dasil003]

That's it, but you cheated :)

I had to spend half an hour debugging a bizarre side effect of that parsing to pinpoint the problem.

[antihero]

That is utterly stupid isn't it, how could the designers of YAML count a capital "NO" as a key as False. Wow.

Edit, holy fuck all these are booleans:

y|Y|yes|Yes|YES|n|N|no|No|NO |true|True|TRUE|false|False|FALSE |on|On|ON|off|Off|OFF