Python Class Members Initialization

Question

I have just recently battled a bug in Python. It was one of those silly newbie bugs, but it got me thinking about the mechanisms of Python (I\'m a long time C++ programmer,

Answer 1

What you keep referring to as a bug is the documented, standard behavior of Python classes.

Declaring a dict outside of __init__ as you initially did is declaring a class-level variable. It is only created once at first, whenever you create new objects it will reuse this same dict. To create instance variables, you declare them with self in __init__; its as simple as that.