'Lists volumes of the disks in the image repository that are
associated with the specified subscription.
Pass Node object to scope the list of volumes to a single
instance.
:rtype: ``list`` of :class:`StorageVolume`'

def list_volumes(self, node=None):

    data = self._perform_get(self._get_disk_path(), Disks)
    volumes = [self._to_volume(volume=v, node=node) for v in data]
    return volumes
