[Answer]-How to perform a specific task in django automatically after a fixed interval of time?

You can use Celery for this, but it is probably overkill if you just have simple task.
http://celery.readthedocs.org/en/latest/userguide/periodic-tasks.html

A simple solution would be to create a django management task wich update the song raking and call it with a cron every ten minutes.

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