Reuse failed Polaroids

Maybe, won't be the first time that if we have a Polaroid camera, we shot a few pictures wrong, because we have gone from light or lack of it.

A very good solution that Gemma from Submarines and Sewing Machines proposes, is to reuse them inserting the picture we want, simply by opening them from the top behind and glue them again! What could be simpler than that?