A very impressing, slow rhythm of jazz, reflecting a person feeling blue and empty in the very early morning hours, perhaps after a long night of crazy partying - or after a tedious night shift at work ...
It is not the same music, not the same rhythm and much later - but it reminds of a similar lonely spirit's feeling after a long night awake:
(info) https://en.wikipedia.org/wiki/Il_est_cinq_heures,_Paris_s%27%C3%A9veille
or, with a different, even softer rhythm, of Debussy, like "Rêverie":