Hello ,
TreeSpirit found her : died in LE CANNET , Alpes Maritimes, not in CANNES.
Still, the deaths in Le Cannet are on line till 1939.
If you want her death cert , write to the service d'état civil of the mairie of LE CANNET (Hôtel de ville - 20 Boulevard Carnot, 06110 Le Cannet ) and ask them to send it to you ( by mail if they prefer , Tree Spirit gave the number of the cert). It's free and anybody can ask for the death cert of anybody and there is no delay in France.
For her will or probate only heirs can have a copy of it .