'Return a list of available pre-installed library drives.
Note: If you want to list all the available library drives (both
pre-installed and installation CDs), use :meth:`ex_list_library_drives`
method.'

def list_images(self):

    response = self.connection.request(action='/libdrives/').object
    images = [self._to_image(data=item) for item in response['objects']]
    images = [image for image in images if (image.extra['image_type'] == 'preinst')]
    return images
