Between the Stronglight and Atax components and the Simplex dropouts it is most likely French, not Italian. Measure the bottom bracket shell width and remove the bottom bracket to check threading. A French bb shell will be 68mm and Italian will be 70mm.
Also check the seatpost size and tubing outer diameter to see if it is metric tubing or inch tubing. If metric it is most likely a French frame.
Likewise the steerer tube inner diameter and threading will tell you French or Italian.
Another hint: if the crankset is original, it will be helpful to note the pedal threading. French thread will certainly indicate a French bike, but English threads don't discount it being French. Many French imports to the US in the 70s came with English-threaded cranks.
Last edited by TenGrainBread; 11-09-19 at 10:27 PM.