I vote against Gitane: a frame with Campy 1010 dropouts would have to be a Super Corsa (or an unusual TdF) and this frame does not have any details that match those 2 models. Doesn't ring any definite big-name French bells (not a Moto, or a Peugeot) so then you're into the more obscure: I can't say whether Mercier is a good guess, might be, but it would have to be a model 300 (which normally has Simplex DOs and ends). Stella, Bertin, Follis...none of those hits me as a match. Serial number or other details are gonna be necessary: forkcrown (is it a Vagner?) bridges, etc.