def process(value):
            """
            return the actual value after processing
            """
            if attr.startswith("__"):
                # __repr__, __str__ etc
                return getattr(value, attr)(*args, **kw)
            else:
                # upper, lower etc
                return getattr("".__class__, attr)(value, *args, **kw)

            return the actual value after processing
            
py3status/private.py