At the end of the rare Truffaut short Antoine et Colette (which is a sequel to 400 Blows), there is a beautiful and bittersweet(and brief!) song written by frequent Truffaut collaborator, Georges Delerue. The song is accompanied by still shots (very much in the style of Henri Cartier-Bresson's photos) of lovers in Paris. The song begins at 0:52:

When You\'re 20 and in Love

For those that are interested in seeing the whole short, here are the links (with English subtitles):

Antoine et Colette, Part 1

Antoine et Colette, Part 2

Antoine et Colette, Part 3
_________________________
She was with me even in my grave
When the last of my friends turned away,
And she sang like the first storm heaven gave.
Or as if flowers were having their say.

- Anna Akhmatova, "Music"(Dedicated to Dmitri Shostakovich)