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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _storage_purge_all(delete=False, verbosity=0):
 """Purge unreferenced storages."""

    orphaned_storages = Storage.objects.filter(data=None)

    if verbosity >= 1:
        if orphaned_storages.exists():
            logger.info(__("Unreferenced storages ({}):", orphaned_storages.count()))
            for storage_id in orphaned_storages.values_list('id', flat=True):
                logger.info(__("  {}", storage_id))
        else:
            logger.info("No unreferenced storages")

    if delete:
        orphaned_storages.delete()