Traceback (most recent call last): File "plugin.py", line 28, in <module> class Fontbold(FilterWithDialog): objc.BadPrototypeError: Objective-C expects 1 arguments, Python argument has 2 arguments

[FlorianPircher]

I think this should also be solved by this:

How to call a custom function

Python methods expect the first parameter to be the self object. For example: def angle_between_points(self, point1, point2):