'A ``KeyError`` is raised if ID can\'t be calculated.'

def test_unknown_ip(self):

    local_ips = {ipaddress_from_string('192.0.0.1'), ipaddress_from_string('10.0.0.1')}
    reported_ips = {u'server2': {ipaddress_from_string('192.0.0.2')}}
    self.assertRaises(KeyError, _get_compute_id, local_ips, reported_ips)
