Hi everyone, I possibly found a bug in class initialization and would like to fix it. Because it's my first journey to core-dev, I would really appreciate the help of a mentor that I may ask a few questions to get me up to speed. To my person, I have previously worked on larger projects in python, c, and c++ if that information helps, and I'm really curious to learn more about the interiors of the greatest interpreter known to wo-/men. Here comes the bug-producing example: `class Foo: def __init__(self, bar=[]): self.list = bar spam_1 = Foo() spam_2 = Foo() spam_1.list.append(42) print(spam_2.list)` At least I think it's a bug. Maybe it's a feature.. Best Regards, Jus --- f*** me <https://github.com/jusjusjus> on github :)