'Return a dictionary keyed with \'deleted\', \'hidden\', and \'active\' with values
for each representing the count of contents in each state.
Note: counts for deleted and hidden overlap; In other words, a dataset that\'s
both deleted and hidden will be added to both totals.'

def serialize_contents_active(self, history, key, **context):

    return self.manager.contents_manager.active_counts(history)
