The title is a direct reference to Magritte's La Trahison des Images (The Treachery of Images), made in 1928. This painting shows a realistic image of a pipe, but on the canvas is written: 'Ceci n' est pas une Pipe'. He wants to remind the viewer that there is no real pip, that it's only canvas and oil.
(This is not a) Love Song of Nouvelle Vague, This is not a Photograph by Diego Fazio, This is not a Film from Jafar Panahi and Mojtaba Mirtahmasb; 'This is not a' is acquired by people from all over the world. But the meaning of those four words differs in every sentence that is constructed with them. In case of the love song it can be interpret as 'Yes it is, but a very exclusive one'. Sometimes it means 'I just don't know what to call it'. When it comes to the painting that looks like a photograph, it says: 'Look, I did something that most people can't'. And so on.