def init(policy_file=None, rules=None, default_rule=None, use_conf=True):

    global _ENFORCER
    if not _ENFORCER:
        _ENFORCER = policy.Enforcer(CONF,
                                    policy_file=policy_file,
                                    rules=rules,
                                    default_rule=default_rule,
                                    use_conf=use_conf)
uses current model empirical estimates to forecast which index is the winner
dataset/ETHPy150Open BU-NU-CLOUD-SP16/Trusted-Platform-Module-nova/nova/policy.py/init--crossover with--dataset/ETHPy150Open nextml/NEXT/next/apps/DuelingBanditsPureExploration/Prototype.py/DuelingBanditsPureExplorationPrototype.predict