I got some lovely French stamps from my sister-in-law Els and her partner Gérard (merci encore!) who live in France, and was very happy with this one:

It is a stamp which is not often included in Marianne de Gandon lists, probably because it has no direct link to the definitive set. It is a commemorative stamp marking the French heritage year 1980. But be that as it may, it still has an image of the definitive set as large part of the design! And you may be fooled when only glancing over it, but when you mirror the image there's no mistaking!

It is absolutely a copy of the Marianne set!

So that made my day!