For loop in my __init__ doesn't work as expected

[ichabod801]

When you loop through a dictionary, each time through the loop you get one key. You assign that to self.keys, but each time you do it, you overwrite what was there before. So whatever the last key is, that's what self.keys ends up as.

If you want all of the keys, I would suggest self.keys = list(self.key_values.keys())