'List all compute services and add them all to an aggregate.'

def _add_hosts_to_aggregate(self):

    compute_services = [s for s in self.api.get_services() if (s['binary'] == 'nova-compute')]
    agg = {'aggregate': {'name': 'test-aggregate'}}
    agg = self.api.post_aggregate(agg)
    for service in compute_services:
        self.api.add_host_to_aggregate(agg['id'], service['host'])
    return len(compute_services)
