Sorry for being silly, I just realize that I should have tried match.start and match.end, but now I have to leave my beloved computer.
I have a problem with the forst one: although I can write the old text on screen and ask for a choice, I cannot present the environment of the match. So I have either to give a blind answer or open tha page in a browser firt which makes the process slow down. After I have given the choices for all the matches, replace.py will print a showDiff, but not before I choose.