#!/usr/bin/env python import chardataeffect, inkex, string class C(chardataeffect.CharDataEffect): def process_chardata(self,text, line, par): r = "" for i in range(len(text)): c = text[i] if c.islower(): r = r + c.upper() elif c.isupper(): r = r + c.lower() else: r = r + c return r c = C() c.affect()