luck out of (something)
To avoid having to do or experience something because of some fortunate chance occurrence. Thankfully, because school was closed due to the weather, I lucked out of taking the exam I hadn't studied for. I can't believe you lucked out of doing an inventory count like the rest of us.
luck out of something
to get out of something by luck alone. I lucked out of taking a driving test. I only had to pass a vision test to get my license. Man, I really lucked out of it.