I'm not regularly a python developer and I just spent a ton of time earlier this week tripped up by the default argument being a stored value. I was using to m

I'm not regularly a python developer and I just spent a ton of time earlier this week tripped up by the default argument being a stored value. I was using to make an empty set if no set was passed in... but the set was not always empty because it was being reused. Took me forever to figure out what was going on.