How to use the magent.utility.piecewise_decay function in magent

print("load ... %d" % start_from)
        for model in models:
            model.load(savedir, start_from)
    else:
        start_from = 0

    # print debug info
    print(args)
    print("view_space", env.get_view_space(handles[0]))
    print("feature_space", env.get_feature_space(handles[0]))

    # play
    start = time.time()
    for k in range(start_from, start_from + args.n_round):
        tic = time.time()
        eps = magent.utility.piecewise_decay(k, [0, 200, 400], [1, 0.2, 0.05]) if not args.greedy else 0

        loss, reward, value = play_a_round(env, args.map_size, handles, models,
                                           print_every=50, train=args.train,
                                           render=args.render or (k+1) % args.render_every == 0,
                                           eps=eps)  # for e-greedy
        log.info("round %d\t loss: %s\t reward: %s\t value: %s" % (k, loss, reward, value))
        print("round time %.2f  total time %.2f\n" % (time.time() - tic, time.time() - start))

        if (k + 1) % args.save_every == 0 and args.train:
            print("save model... ")
            for model in models:
                model.save(savedir, k)

    # send quit command
    for model in models:
        model.quit()

print("load ... %d" % start_from)
        models[0].load(savedir, start_from)
    else:
        start_from = 0

    # print debug info
    print(args)
    print("view_size", env.get_view_space(handles[0]))
    print("feature_size", env.get_feature_space(handles[0]))

    # play
    start = time.time()
    for k in range(start_from, start_from + args.n_round):
        tic = time.time()
        start = 1 if args.opponent != -1 else 0.1
        train_eps = magent.utility.piecewise_decay(k, [0, 100, 250], [start, 0.1, 0.05]) if not args.greedy else 0
        opponent_eps = train_eps if k < 100 else 0.05  # can use curriculum learning in first 100 steps

        loss, num, reward, value = play_a_round(env, args.map_size, handles, models,
                                                eps=[opponent_eps, train_eps], step_batch_size=step_batch_size,
                                                train=args.train,
                                                print_every=50,
                                                render=args.render or (k+1) % args.render_every == 0)  # for e-greedy

        log.info("round %d\t loss: %s\t num: %s\t reward: %s\t value: %s" % (k, loss, num, reward, value))
        print("round time %.2f  total time %.2f\n" % (time.time() - tic, time.time() - start))

        # save models
        if (k + 1) % args.save_every == 0 and args.train:
            print("save model... ")
            if not os.path.exists(savedir):
                os.mkdir(savedir)

print("load ... %d" % start_from)
        for model in models:
            model.load(savedir, start_from)
    else:
        start_from = 0

    # print state info
    print(args)
    print("view_space", env.get_view_space(handles[0]))
    print("feature_space", env.get_feature_space(handles[0]))

    # play
    start = time.time()
    for k in range(start_from, start_from + args.n_round):
        tic = time.time()
        eps = magent.utility.piecewise_decay(k, [0, 700, 1400], [1, 0.2, 0.05]) if not args.greedy else 0
        loss, num, reward, value = play_a_round(env, args.map_size, handles, models,
                                                train=args.train, print_every=50,
                                                render=args.render or (k+1) % args.render_every == 0,
                                                eps=eps)  # for e-greedy

        log.info("round %d\t loss: %s\t num: %s\t reward: %s\t value: %s" % (k, loss, num, reward, value))
        print("round time %.2f  total time %.2f\n" % (time.time() - tic, time.time() - start))

        # save models
        if (k + 1) % args.save_every == 0 and args.train:
            print("save model... ")
            for model in models:
                model.save(savedir, k)

    # send quit command
    for model in models:

print("load ... %d" % start_from)
        for model in models:
            model.load(savedir, start_from)
    else:
        start_from = 0

    # print debug info
    print(args)
    print("view_space", env.get_view_space(handles[0]))
    print("feature_space", env.get_feature_space(handles[0]))

    # play
    start = time.time()
    for k in range(start_from, start_from + args.n_round):
        tic = time.time()
        eps = magent.utility.piecewise_decay(k, [0, 700, 1400], [1, 0.2, 0.05]) if not args.greedy else 0
        loss, num, reward, value = play_a_round(env, args.map_size, handles, models,
                                                train=args.train, print_every=50,
                                                render=args.render or (k+1) % args.render_every == 0,
                                                eps=eps)  # for e-greedy

        log.info("round %d\t loss: %s\t num: %s\t reward: %s\t value: %s" % (k, loss, num, reward, value))
        print("round time %.2f  total time %.2f\n" % (time.time() - tic, time.time() - start))

        # save models
        if (k + 1) % args.save_every == 0 and args.train:
            print("save model... ")
            for model in models:
                model.save(savedir, k)

if args.record:
        for k in range(4, 999 + 5, 5):
            eps = 0
            for model in models:
                model.load(save_dir, start_from)
                play_a_round(env, args.map_size, food_handle, player_handles, models,
                             -1, record=True, render=False,
                             print_every=args.print_every, eps=eps)
    else:
        # play
        start = time.time()
        train_id = 0 if args.train else -1
        for k in range(start_from, start_from + args.n_round):
            tic = time.time()
            eps = magent.utility.piecewise_decay(k, [0, 400, 1000], [1.0, 0.2, 0.05]) if not args.greedy else 0
            loss, reward, value, pos_reward_ct = \
                    play_a_round(env, args.map_size, food_handle, player_handles, models,
                                 train_id, record=False,
                                 render=args.render or (k+1) % args.render_every == 0,
                                 print_every=args.print_every, eps=eps)
            log.info("round %d\t loss: %.3f\t reward: %.2f\t value: %.3f\t pos_reward_ct: %d"
                     % (k, loss, reward, value, pos_reward_ct))
            print("round time %.2f  total time %.2f\n" % (time.time() - tic, time.time() - start))

            if (k + 1) % args.save_every == 0 and args.train:
                print("save models...")
                for model in models:
                    model.save(save_dir, k)

print("load ... %d" % start_from)
        for model in models:
            model.load(savedir, start_from)
    else:
        start_from = 0

    # print state info
    print(args)
    print("view_size", env.get_view_space(handles[0]))
    print("feature_size", env.get_feature_space(handles[0]))

    # play
    start = time.time()
    for k in range(start_from, start_from + args.n_round):
        tic = time.time()
        eps = magent.utility.piecewise_decay(k, [0, 700, 1400], [1, 0.2, 0.05]) if not args.greedy else 0

        loss, num, reward, value = play_a_round(env, args.map_size, handles, models,
                                                train=args.train, print_every=50,
                                                render=args.render or (k+1) % args.render_every == 0,
                                                eps=eps)  # for e-greedy
        log.info("round %d\t loss: %s\t num: %s\t reward: %s\t value: %s" % (k, loss, num, reward, value))
        print("round time %.2f  total time %.2f\n" % (time.time() - tic, time.time() - start))

        # save models
        if (k + 1) % args.save_every == 0 and args.train:
            print("save model... ")
            for model in models:
                model.save(savedir, k)

    # send quit command
    for model in models:

if args.record:
        for k in range(4, 999 + 5, 5):
            eps = 0
            for model in models:
                model.load(save_dir, start_from)
                play_a_round(env, args.map_size, food_handle, player_handles, models,
                             -1, record=True, render=False,
                             print_every=args.print_every, eps=eps)
    else:
        # play
        start = time.time()
        train_id = 0 if args.train else -1
        for k in range(start_from, start_from + args.n_round):
            tic = time.time()
            eps = magent.utility.piecewise_decay(k, [0, 400, 1200], [1.0, 0.2, 0.10]) if not args.greedy else 0
            loss, reward, value, pos_reward_ct, fill_rate = \
                play_a_round(env, args.map_size, food_handle, player_handles, models,
                             train_id, record=False,
                             render=args.render or (k+1) % args.render_every == 0,
                             print_every=args.print_every, eps=eps)
            log.info("round %d\t loss: %.3f\t reward: %.2f\t value: %.3f\t pos_reward_ct: %d\t fill: %.2f"
                     % (k, loss, reward, value, pos_reward_ct, fill_rate))
            print("round time %.2f  total time %.2f\n" % (time.time() - tic, time.time() - start))

            if (k + 1) % args.save_every == 0 and args.train:
                print("save models...")
                for model in models:
                    model.save(save_dir, k)

print("load ... %d" % start_from)
        for model in models:
            model.load(savedir, start_from)
    else:
        start_from = 0

    # print debug info
    print(args)
    print("view_space", env.get_view_space(handles[0]))
    print("feature_space", env.get_feature_space(handles[0]))

    # play
    start = time.time()
    for k in range(start_from, start_from + args.n_round):
        tic = time.time()
        eps = magent.utility.piecewise_decay(k, [0, 700, 1400], [1, 0.2, 0.05]) if not args.greedy else 0
        loss, num, reward, value = play_a_round(env, args.map_size, handles, models,
                                                train=args.train, print_every=50,
                                                render=args.render or (k+1) % args.render_every == 0,
                                                eps=eps)  # for e-greedy

        log.info("round %d\t loss: %s\t num: %s\t reward: %s\t value: %s" % (k, loss, num, reward, value))
        print("round time %.2f  total time %.2f\n" % (time.time() - tic, time.time() - start))

        # save models
        if (k + 1) % args.save_every == 0 and args.train:
            print("save model... ")
            for model in models:
                model.save(savedir, k)