'View of volumes summary.
It includes number of volumes, size of volumes and all distinct
metadata of volumes.'

def quick_summary(self, volume_count, volume_size, all_distinct_metadata=None):

    summary = {'volume-summary': {'total_count': volume_count, 'total_size': volume_size}}
    if (all_distinct_metadata is not None):
        summary['volume-summary']['metadata'] = all_distinct_metadata
    return summary
